Conflict & Security in the 9th century

315 sourced entries, 800 CE to 899 CE, oldest first. Also see Conflict & Security across every century or everything else in the 9th century.

• 800The Abbasid Caliphate is forced to cede Ifriqiya (present-day north-eastern Algeria, Tunisia and western Libya) to the Aghlabid Dynasty.source
• 800The Abbasid Caliphate is forced to cede their holdings in southern Italy to the Aghlabid Dynasty.source
• 801April 3 – King Louis the Pious, son of Charlemagne, captures Barcelona after a siege of several months. Bera is appointed first count of Barcelona.source
• 801King Eardwulf of Northumbria leads an army into Mercia against his rival, Coenwulf, in order to flush out other claimants to the Northumbrian throne.source
• 801Emperor Charlemagne formally cedes Nordalbian territory (modern-day Schleswig-Holstein) to the pagan Obotrites (allies of the Carolingian Empire).source
• 802Pagan Danes invade Obodrite-ruled Schleswig, to take over territory almost emptied by the forcible deportations of the Saxons by emperor Charlemagne.source
• 802Al-Andalus: Saragossa rises against the Emirate of Córdoba. Emir Al-Hakam I sends a Muslim army under General Amrus ibn Yusuf, and retakes the city.source
• 802Battle of Kempsford: Æthelmund, ealdorman of Hwicce, is killed during the battle by his rival Weohstan, who levies West Saxon Wiltshire.source
• 803May – Krum, ruler (khan) of the Bulgarian Empire, begins his territorial expansion and raids the Byzantine northern frontier. He leads his warriors — mostly Bulgars, Slavs, Thracians and Macedonians — across the Carpathian Mountains, over the Danube River, and throughout Transylvania, Thrace, and Macedonia.source
• 803Summer – Bardanes Tourkos, Byzantine general (strategos), is proclaimed emperor by the troops of the Anatolic, Opsikion, Thracian and Bucellarian themes. The 'rebel' army marches to Chrysopolis, a suburb of Constantinople. After the defection of two of his trusted aides, future emperors Leo the Armenian and Michael the Amorian, Bardanes negotiates peace.source
• 804Summer – Emperor Charlemagne finishes the conquest of Saxony. The Carolingian administration in the north is restored and the diocese of Bremen is re-established. Venice, torn by infighting, switches allegiance from Constantinople to King Pepin of Italy, son of Charlemagne.source
• 804Battle of Krasos: Emperor Nikephoros I refuses to pay the tribute imposed by Caliph Harun al-Rashid of the Abbasid Caliphate. A Muslim-Arab expeditionary force invades Asia Minor. During a surprise attack, Nikephoros suffers a major defeat against the Saracens at Krasos in Phrygia. According to Arabian sources, the Byzantines lose 40,700 men and 4,000 pack animals, while Nikephoros himself is almost killed, but saved by the bravery of his officers.source
• 805Siege of Patras: Local Slavic tribes of the Peloponnese lay siege to the city of Patras (modern Greece), with aid from an Arab fleet. A Byzantine relief army under Skleros, military governor (strategos) from Corinth, is sent and retakes the city. The captured Slavs in Patras are made slaves, and a church is dedicated to St. Andrew.source
• 805Siege of Canburg: The Franks under Charles the Younger, son of emperor Charlemagne, unsuccessfully besiege Bohemians near the modern-day town of Kadaň.source
• 805Krum, ruler (khan) of the Bulgarian Empire, conquers and destroys the Eastern part of the Avar Khaganate (approximate date).source
• 806November – Al-Hakam I, Umayyad emir of Córdoba, reasserts his control over the city of Toledo, autonomous since 797. To this effect Al-Hakam has over 72 nobles (accounts talk of 5,000) massacred at a banquet, crucified and displayed along the banks of the Guadalquivir River (modern Spain), in what comes to be known as the "Day of the Trench".source
• 806Vikings massacre Columba's monks, and all the inhabitants on the island of Iona (Scotland). Other monks flee to safety in the monastery of Kells (Ireland). They take with them the Book of Kells.source
• 806Rafi ibn al-Layth, an Arab nobleman, leads a large-scale rebellion against oppressive taxation by the Abbasid governor Ali ibn Isa ibn Mahan. He launches a revolt in Samarkand, which spreads quickly across Khorasan.source
• 806Arab–Byzantine wars: An Abbasid fleet under Humayd ibn Ma'yuf al-Hajuri raids Cyprus, carrying off 16,000 inhabitants as slaves.source
• 806Arab–Byzantine wars: Caliph Harun al-Rashid leads a huge military expedition, assembling men from Syria, Palestine, Persia, and Egypt. The invasion army (reportedly 135,000 men) departs from Raqqa, residence of Harun, and enters Cappadocia through the Cilician Gates, sacking several Byzantine fortresses and cities. Heraclea is captured after a month-long siege (August/September). The city is plundered and razed; its inhabitants are enslaved and deported to the Abbasid Caliphate.source
• 807Al-Andalus (modern Spain): An uprising occurs in the city of Mérida against the Umayyad Emirate of Córdoba.source
• 807Siege of Patras: This marks the end of independent rule by the South Slavs in the Peloponnese (or 805).source
• 808In Gharb al-Andalus (modern Portugal), Hazim ibn Wahb leads a rebellion against the Emirate of Córdoba.source
• 808Emperor Charlemagne gives orders to construct two new forts on the Elbe River, garrisoning them against future Slav incursions.source
• 808Viking Age: First Viking raid, by Danes against the Baltic coast. Godfred destroys the Slav settlement of Reric (near present-day Wismar), used as a strategic trade route. The population is displaced or abducted, to Hedeby (Denmark).source
• 809Spring – Siege of Serdica: Krum, ruler (khan) of the Bulgarian Empire, captures the fortress of Serdica (modern Sofia), after a long siege. According to Byzantine sources, he massacres the garrison (supposedly 6,000 men), sacks the city, and razes the city walls, before returning with much loot to Bulgaria. In the following years (and centuries), Serdica will serve as a base for the expansion of the Bulgars to the south of the Balkans.source
• 809A rebellion in Gharb al-Andalus (modern Portugal) is crushed by the Emirate of Córdoba.source
• 809A Byzantine fleet lands in the Venetian Lagoon, and attacks a Frankish flotilla at Comacchio, but is defeated. Doge Obelerio degli Antenori marries a Frankish bride, Carola; she becomes the first dogaressa of Venice.source
• 809Emperor Govinda III defeats his rival Nagabhata II, and obtains the submission of the Pala Empire (India).source
• 810Al-Andalus (modern Spain): The city of Mérida rises up against the Emirate of Córdoba.source
• 810Spring – The Venetian dukes change sides again, submitting to King Pepin, under the authority of his father Charlemagne, who then proceeds to take Venice. Emperor Nikephoros I sends a Byzantine fleet to Dalmatia, prompting Pepin to withdraw to the mainland. A legate is dispatched to Venice, where he deposes the turncoat dukes, before continuing on to Aachen, to negotiate a peace with Charlemagne. Charlemagne recognises Byzantine dominance over Venice and Dalmatia in the Adriatic Sea.source
• 811July 23 – Nikephoros I reaches Pliska, and destroys a Bulgarian army of 12,000 elite soldiers who guard the stronghold. Another hastily assembled relief force of 50,000 soldiers suffers a similar fate. The Byzantines capture the defenseless capital. Nikephoros plunders the city and captures Krum's treasury. He burns the countryside, slaughters sheep and pigs, as he pursues the retreating Bulgars southwest towards Serdica (modern-day Sofia).source
• 811July 26 – Battle of Vărbitsa Pass: Nikephoros I is trapped (probably in the Vărbitsa Pass) and defeated by the Bulgars, who use the tactics of ambush and surprise night attacks to immobilize the Byzantine forces. Nikephoros himself is killed; Krum has the emperor's head carried back in triumph on a pole, where it is cleaned out, lined with silver and made into a jeweled skull cup, which he allows his Slavic princes (archons) to drink from with him.source
• 811Stauracius is installed as emperor at Adrianople (the first time a Byzantine emperor is crowned outside Constantinople). Because of a sword wound near his neck (during the Battle of Pliska), Stauracius is paralyzed. The imperial court is split between the noble factions of his wife Theophano and his sister Prokopia.source
• 811Byzantine–Bulgarian War: Emperor Nikephoros I organises a new campaign against the Bulgarian Empire, gathering an expeditionary force (most of the Roman army) from all parts of the empire. He is accompanied by high-ranking officials and aristocrats, including his son Stauracius and brother-in-law Michael I Rangabe (both later emperors temporarily). Krum, ruler (khan) of Bulgaria, sends envoys to sue for peace. Nikephoros refuses to accept the terms and marches through the Balkan passes towards Pliska, the Bulgarian capital.source
• 812Byzantine–Bulgarian War: The Bulgars, led by Krum, ruler (khan) of the Bulgarian Empire, launch an invasion against the Byzantines. They capture the fortress cities of Develt and Mesembria, near the Black Sea.source
• 812The Republic of Amalfi sends galleys to support the Byzantine general (strategos) of Sicily, Gregorio, against the Aghlabid invaders. It is one of the earliest evidences of the independence of the city.source
• 812King Sigered of Essex is reduced to the rank of duke, by his Mercian overlords.source
• 812Fourth Fitna: Forces loyal to al-Ma'mun, led by Tahir ibn Husayn, blockade Baghdad, which is loyal to al-Ma'mun's brother, Caliph al-Amin, and begin the year-long Siege of Baghdad.source
• 813June 22 – Battle of Versinikia: The Bulgars, led by Krum, ruler (khan) of the Bulgarian Empire, defeat Emperor Michael I near Edirne (modern Turkey). The Byzantine army (26,000 men) is destroyed by a counter-attack of Bulgarian heavy cavalry, while trapped in the valley. Krum captures the Byzantine camp and a rich prize, including gold and weaponry.source
• 813Danish Viking raiders, led by King Horik I, attack Vestfold (modern Norway), due to its insubordination (approximate date).source
• 813Autumn – Siege of Baghdad: Caliph al-Amin surrenders Baghdad, after al-Ma'mun's General Tahir accepts his peace terms, but he is captured and executed. His brother al-Ma'mun becomes undisputed ruler of the Abbasid Caliphate.source
• 813Autumn – Siege of Adrianople: Krum captures Adrianople—one of the most important Byzantine fortresses in Thrace—after being attacked with siege engines. The garrison is forced to surrender, due to starvation. On the orders of Krum, the population of the surrounding area (numbering about 10,000) is transferred to Bulgarian territory, north of the Danube.source
• 816Battle of Pancorbo: A Moorish army from the Emirate of Córdoba is sent by Emir Al-Hakam I, to take control of the pass at Pancorbo. They defeat the army of Asturian-Basque Frankish vassals.source
• 816Babak Khorramdin, Persian military leader, revolts against the Abbasid Caliphate in Azerbaijan (approximate date).source
• 816Vikings raid Ireland at the Kingdom of Munster, at Inish Cathaigh.source
• 816Winter – The Basques, supported by the Moors, cross the Garonne River and revolt against the Franks in Gascony (north of the Pyrenees).source
• 816King Hywel of Gwynedd is attacked by his brother Cynan on Anglesey (modern Wales), who is killed during the fighting (approximate date).source
• 817Prince Grimoald IV is assassinated by a complot of Lombard nobles vying for his throne. He is succeeded by Sico as ruler of Benevento (Southern Italy), who is forced to pay an annual tribute of 7,000 solidi to Louis I.source
• 817Ziyadat Allah I becomes the third Aghlabid emir of Ifriqiya (modern Tunisia). During his rule, the relationship between the Aghlabid Dynasty and the Arab troops remains strained.source
• 818Al-Andalus: A grave rebellion breaks out in the suburbs of Cordoba, against the Emirate of Córdoba. Andalucian Arab refugees arrive in Fez (modern Morocco).source
• 818The Anglo-Saxons, led by King Coenwulf of Mercia, raid Dyfed in Wales (approximate date).source
• 819Battle of Kupa: Ljudevit defeats the Frankish forces led by Borna, a vassal of Louis I. He escapes with the help of his elite bodyguard. Ljudevit uses the momentum and invades the Duchy of Croatia.source
• 819Ghassan ibn Abbad, the Abbasid governor of Khorasan rewards the Samanid brothers, Nuh, Ahmad, Yahya and ilyas for their aid against the rebel Rafi ibn al-Layth, rewarding them each important cities and territories, respectively Samarkand, Farghana, Tashkent and Herat, to govern under Abbasid suzerainty. This becomes the basis for the formation of the Samanid dynasty which will rule Khorasan for a century.source
• 819Ljudevit, duke of the Slavs in Lower Pannonia, raises a rebellion against the Frankish Empire. Louis I sends an army led by Cadolah of Friuli, but is defeated by the Pannonian Slavs.source
• 822Battle of Kedouktos (near Heraclea): Khan Omurtag of Bulgaria sends a relief army, and defeats the Byzantine rebels.source
• 822Kim Hŏn-ch'ang launches a short-lived rebellion in Silla, which gains control over much of the southern and western Korean Peninsula.source
• 822King Ceolwulf I of Mercia invades Powys (Wales), but is beaten back by King Cyngen. However, Ceolwulf does destroy the fortress of Deganwy, and later takes the kingdom under his control (approximate date).source
• 822Byzantine general and usurper Thomas the Slav continues his revolt against Emperor Michael II. He unsuccessfully besieges Constantinople, while his fleet is destroyed by Michael's fleet, using Greek fire.source
• 823Emperor Michael II defeats the rebel forces under Thomas the Slav in Thrace. He and his supporters are forced to seek refuge in Arkadiopolis (modern Turkey). After five months of blockade, Thomas surrenders and is delivered to Michael, seated on a donkey and bound in chains. He pleads for clemency and prostrates before Michael, but is executed.source
• 824February 8 – The Tenchō era begins in Japan at the beginning of the reign of the Emperor Junna, bringing an end to the Kōnin era after 15 years.source
• 824September – Rebellious Arab troops in North Africa, led by Mansur ibn Nasr al-Tunbudhi in a battle against the Aghlabids, led by the Emir Ziyadat Allah, invade and occupy the city of Tunis.source
• 824Vikings raid Ireland, on the Kingdom of Munster at Skellig Michaelsource
• 824Battle of Roncevaux Pass: The Basques and Banu Qasi defeat a Frankish expedition, led by Counts Aznar and Ebles, in the Pyrenees.source
• 825Battle of Gafulford: The men of Cornish Dumnonia clash with the West Saxons at modern-day Camelford (approximate date).source
• 825Emperor Louis the Pious begins a military campaign against the Wends and Sorbs. Duke Tunglo surrenders his son as hostage, and submits to Frankish rule (approximate date).source
• 825Battle of Ellandun: King Egbert of Wessex defeats Beornwulf of Mercia near Swindon. The battle marks the end of the Mercian domination of southern England. The kingdoms of Kent, Surrey, Sussex and Essex submit to Wessex, and East Anglia acknowledges Egbert as overlord (bretwalda).source
• 826May – Euphemius, Byzantine admiral, organises an uprising in Sicily against Emperor Michael II. He proclaims himself Emperor (with the title of basileus) in Syracuse, independent from Constantinople. In turn, Euphemius is defeated by Byzantine troops (reinforcements from the East), and is driven out to North Africa.source
• 826King Beornwulf of Mercia invades East Anglia, but is killed in battle. He is succeeded by Ludeca, as ruler of Mercia.source
• 826Prince Aethelwulf, a son of King Egbert of Wessex, invades Kent, and drives out its pro-Mercian king Baldred.source
• 827Giustiniano Participazio deposes his younger brother Giovanni I, and is appointed doge of Venice. Giovanni, who is part of a pro-Frankish faction, is exiled to Zara (modern Croatia).source
• 827Fall – Siege of Syracuse: Muslim forces under Asad ibn al-Furat, in support of the rebel Byzantine army, besiege Syracuse, Sicily.source
• 827Emperor Jing Zong is assassinated by a group of conspirators. He is succeeded by his brother Wen Zong, as ruler of the Tang Dynasty.source
• 827Summer – Omurtag, ruler (khan) of the Bulgarian Empire, launches an attack to the West, and penetrates into Pannonia. He expels the local chiefs, and installs Bulgar governors over the Slavic tribes to control them. Omurtag conquers the cities of Beograd, Braničevo, Sirmium, and most of eastern Slavonia.source
• 827Æthelstan establishes himself as king of East Anglia, after killing King Ludeca of Mercia in battle. Ludeca is succeeded by Wiglaf, father-in-law (and probably distant cousin) of the late king Ceolwulf I's daughter.source
• 828A Coptic revolt breaks out in Egypt (approximate date).source
• 828Al-Andalus: The city of Merida (modern Spain) rises twice in one year against the Umayyad Emirate.source
• 828In the capital of Chang'an, a powerful court eunuch orders 50 wrestlers to arrest 300 commoners over a land property dispute in Northwest Chang'an, whereupon a riot breaks out in the streets.source
• 829October – Battle of Thasos: Saracens from the newly founded Emirate of Crete almost annihilate the Byzantine fleet at Thasos, close to the coast of Thrace. The Cyclades and other islands in the Aegean Sea are pillaged.source
• 829The Bai kingdom of Nanzhao captures the city of Chengdu, in Sichuan Province.source
• 829Winter – Battle of the River Dore: Egbert of Wessex leads his army against the Northumbrians as far as Dore, where he clashes with King Eanred of Northumbria.source
• 829King Egbert of Wessex invades Mercia, ousts his rival Wiglaf, and attempts to rule directly from Wessex. He is recognized as overlord (bretwalda) of other English kingdoms.source
• 830Nennius, Welsh abbot of Bangor Fawr, compiles the Historia Brittonum. He is also known for the Historia's list of the 12 battles of King Arthur (approximate date).source
• 830Emperor Louis the Pious returns from a campaign in Brittany, and is captured by his son Pepin I, king of Aquitaine. He is put under house arrest at Compiegne, and his wife Judith is incarcerated at Poitiers.source
• 831Summer – Muslim Arabs under Caliph Al-Ma'mun launch an invasion into Anatolia (modern Turkey), and capture a number of Byzantine forts. Heraclea Cybistra and Tyana fall to the Arabs.source
• 831Fall – Muslim Arabs reinvade Sicily, and lay siege to Palermo. Symeon, Byzantine commander of the imperial bodyguard (spatharios), surrenders the city in exchange for a safe departure.source
• 831Byzantine–Arab War: Emperor Theophilos invades the Abbasid dominions, and reaches the Euphrates River in north-eastern Syria. He captures and sacks the city of Tarsus, but is defeated in Cappadocia.source
• 832Berengar the Wise, count (or duke) of Toulouse, attacks the Frankish domains of Bernard of Septimania, taking Roussillon (along with Vallespir, Razès, and Conflent).source
• 832The Flag of Scotland: According to legend, King Óengus II of Fortriu leads an army of Picts and Scots, against the invading Angles from Northumbria, near Athelstaneford.source
• 832King Pepin I of Aquitaine, and his brother Louis the German, revolt against their father, Emperor Louis the Pious. They gather an army of Slav allies and conquer Swabia.source
• 832Byzantine–Arab War: The Byzantine fortress of Loulon (modern Turkey) is captured by the Abbasids. Its garrison surrenders to Caliph Al-Ma'mun, after a lengthy siege.source
• 833June – Lothair I, eldest son of Emperor Louis the Pious, joins the rebellion of his brothers Pepin I and Louis the German, with the assistance of Archbishop Ebbo. Louis is forced to abdicate, on the plains of Rothfield (near Colmar).source
• 833Byzantine-Arab War: Emperor Theophilos signs an armistice for peace with the Abbasid Caliphate. He offers Caliph Al-Ma'mun 100,000 gold dinars, in return for 7,000 Byzantine prisoners.source
• 833Galindo Aznárez I, Frankish count, usurps the Catalan counties (pagi) of Pallars and Ribagorza, in the Spanish March (modern Spain), a buffer zone between the Pyrenees and the Ebro River.source
• 835The Isle of Sheppey (off the northern coast of Kent) is attacked by Vikings.source
• 835Vikings raid Ireland on the Kingdom of Munster, at Inis Cathaigh.source
• 836July 4 – Pactum Sicardi: Prince Sicard of Benevento signs a 5-year armistice with the duchies of Sorrento, Naples and Amalfi. He recognizes the trade of merchants among the three cities in Southern Italy.source
• 836Battle of Carhampton: Danish Vikings arrive in the Wessex areas of Somerset and North Devon. Ecgberht, King of Wessex fights them but is forced to withdraw.source
• 837The city of Naples (modern Italy) is attacked by Saracens from Egypt demanding an annual payment (approximate date).source
• 837The Slavs in the vicinity of Thessaloniki revolt against the Byzantine Empire. Theophilos undertakes an evacuation of some Byzantine captives, who are settled in trans-Danubian Bulgaria.source
• 837Presian I, ruler (khan) of the Bulgarian Empire, sends his prime-minister Isbul against the Smolyani (a Slavic tribe in Byzantine territory near the Struma River). The Bulgarian army campaigns along the Aegean coasts, and conquers most of Thrace and Macedonia, including the fortress city of Philippi, as recorded in the Presian Inscription.source
• 838Battle of Hingston Down: Ecgberht, King of Wessex, leads his men to defeat a combined force of Cornish and Danish Vikings at Hingston Down in Cornwall.source
• 838The Yazidis rise up against the Abbasids (approximate date).source
• 839Prince Sicard of Benevento is assassinated by a conspiracy among the nobility. He is succeeded by Radelchis I, chief army officer and treasurer of Sicard, who proclaims himself ruler of Benevento. He imprisons Siconulf, heir and brother of Sicard, in Taranto. But Amalfitan merchants, led by Landulf I, the gastald of Capua, and with the support of Guaifer, rescue him from prison. Siconulf is proclaimed prince of Salerno, and a civil war erupts, which splits the Lombard principality in Southern Italy.source
• 839Third Civil War: King Louis the German, grandson of Charlemagne, invades Swabia. His nephew, Pepin II of Aquitaine, and his Gascon subjects, conquer territory all the way to the Loire.source
• 839The Hungarians (also known as Magyars) who until this time have lived east of the Carpathians, raid the Lower Danube at the request of the Bulgarian Empire against the Byzantine insurgents.source
• 839Battle of 839: Eóganan mac Óengusa, King of the Picts, his brother Bran, Áed mac Boanta, King of Dál Riata, "and others almost innumerable" are killed in a battle fought by the men of Fortriu in Scotland against Vikings. Alpín mac Echdach (Alpín II) apparently succeeds Áed.source
• 840The Yenisei Kirghiz settle along the Yenisei River, and sack with a force of around 80,000 horsemen the Uyghur capital, Ordu-Baliq (driving the Uyghurs out of Mongolia). This ends the Uyghur Khaganate.source
• 841June 25 – Battle of Fontenay: Frankish forces of Emperor Lothair I, and his nephew Pepin II of Aquitaine, are defeated by allied forces of King Louis the German, and his half-brother Charles the Bald, at Fontenoy (Eastern France), in a civil war among the three surviving sons of the former emperor Louis the Pious. A total of 40,000 men are killed, including the Frankish nobles Gerard of Auvergne and Ricwin of Nantes, fighting on the side of Charles.source
• 841Constantine Kontomytes, Byzantine general (strategos) of the Thracesian Theme, inflicts a severe defeat on the Cretan Saracens. He leads a Byzantine expeditionary force, to raid the monastic community near Mount Latros (modern Turkey).source
• 841A pro-Umayyad rebellion, led by al-Mubarqa in Palestine, breaks out against caliph al-Mu'tasim of the Abbasid Caliphate (ending in 842).source
• 841Venice sends a fleet of 60 galleys (each carrying 200 men) to assist the Byzantines in driving the Arabs from Crotone, but the attack fails. Muslim troops conquer the city of Brindisi (approximate date).source
• 843May 24 – Battle of Blain: Breton forces under Erispoe, count of Vannes, defeat the Franks led by Renaud d'Herbauges, near the town of Messac, at the River Vilaine. This battle marks a Breton war between Charles the Bald and Nominoe, duke of Brittany.source
• 843Al-Andalus: The city of Zaragossa rises against the Umayyad Emirate of Córdoba in modern-day Spain.source
• 844September 25–November 11 or 17 – Viking raid on Seville (844): Vikings arrive in Seville by the Guadalquivir, taking the city on October 1 or 3 and pillaging it; but are expelled by forces of the Emirate of Córdoba.source
• 844Summer – King Charles the Bald struggles against the repeated rebellions in Aquitaine, and against the Bretons in West Francia. He besieges Bernard I at the Battle of Toulouse, while Duke Nominoe raids into Maine, and plunders other Frankish territory.source
• 844King Æthelred II of Northumbria is expelled from his kingdom by Rædwulf, who takes the throne. Rædwulf is later killed in battle against the Vikings, along with many of his noblemen. Æthelred returns and claims his right to rule.source
• 844Spring – Battle of Mauropotamos: A Byzantine expedition under Theoktistos is sent to Anatolia (modern Turkey), against the Muslim Arabs of the Abbasid Caliphate, who have raided the Byzantine themes of Cappadocia, Anatolikon, Boukellarion, and Opsikion. The Byzantines are defeated, and many of the officers defect to the Arabs.source
• 844Viking raiders ascend the River Garonne as far as the city of Toulouse, and pillage the lands of Septimania. Part of the marauding Vikings invades Galicia (Northern Spain), where some perish in a storm at sea. After being defeated in Corunna, the Scandinavian raiders sack the Umayyad cities of Seville (see below), Niebla, Beja, and Lisbon.source
• 845November 22 – Battle of Ballon: Frankish forces (3,000 men) led by Charles the Bald are defeated by Nominoe, count of Vannes, near Redon, Ille-et-Vilaine. After the battle, Brittany becomes a regnum 'kingdom' within the Frankish Empire.source
• 845Viking forces destroy Hamburg.source
• 845Byzantine–Arab War: A prisoner exchange occurs between the Byzantine Empire and the Abbasid Caliphate, at the River Lamos in Cilicia (modern Turkey). The exchanges last for 10 days, and the Byzantines recover 4,600 prisoners.source
• 846Byzantine–Bulgarian War: The Bulgarians violate the peace treaty (see 815), and invade Macedonia along the River Struma. The cities of Serres and Philippi are devastated.source
• 846King Æthelred II of Northumbria sends military assistance to the Picts, in their fight against the invading Scots (approximate date).source
• 846Summer – Breton forces under Nominoe occupy the Frankish cities of Nantes and Rennes. He makes raids in Anjou and threatens Bayeux. King Charles the Bald recognizes him as duke of Brittany.source
• 846Frankish forces led by Louis the German invade Moravia. They encounter little resistance, and depose King Mojmir I from the throne. His relative, Rastislav, is set up as the new client ruler.source
• 846Chang Pogo, a powerful maritime hegemon of Silla, is assassinated by aristocratic elements at his garrison headquarters by Yŏm Chang (or 841).source
• 847Viking Age: The Vikings plunder the Lower Rhine, as part of their attacks on the Empire of Francia.source
• 847The Saracens, under the Berber leader Kalfun, capture the Byzantine city of Bari (Southern Italy). He becomes the first ruler of the Emirate of Bari, and expands his influence on the Italian mainland with raids.source
• 847Danish Vikings land in the Breton March (western part of Gaul). Duke Nominoe of Brittany fails to withstand them in battle, but succeeds in buying them off with gifts and persuading them to leave (approximate date).source
• 848Máel Sechnaill mac Maíl Ruanaid, High King of Mide, defeats a Norse Viking army at Sciath Nechtain in Ireland (approximate date).source
• 848The armies of Brycheiniog and Gwent clash in the battle of Ffinnant (Wales). King Ithel of Gwent is killed in the fighting (approximate date).source
• 848The Saracens conquer Ragusa (Sicily), after its Byzantine garrison is forced by severe famine to surrender. The city and its castle are razed to the ground.source
• 849Frankish forces under King Charles the Bald invade southern France, and conquer the territory of Toulouse. He appoints Fredelo as count (comté) of Toulouse, who founds the Rouergue dynasty. Aquitaine is submitted to the West Frankish Kingdom.source
• 849Summer – Battle of Ostia: A Saracen Arab fleet from Sardinia sets sail towards Rome. In response, Pope Leo IV forms a coalition of maritime Italian cities, including Naples, Amalfi and Gaeta, led by Admiral Caesar — which is assembled off the re-fortified port of Ostia — and repels the Saracen marauders. Their navy is scattered, resulting in many sunken vessels. Rome is saved from plunder and the expansion of the Aghlabids.source
• 849The Armenian prince Bagrat II begins a rebellion against Caliph Al-Mutawakkil, of the Abbasid Caliphate.source
• 850King Kenneth I (also called Kenneth MacAlpin) of Alba (modern Scotland) invades Northern Northumbria during the period of 850–858, burning Dunbar and Melrose.source
• 850Danish Viking raiders, led by King Rorik, conquer Dorestad and Utrecht (modern-day Netherlands). Emperor Lothair I recognizes him as ruler of most of Friesland.source
• 851Bagrat II Bagratuni, Armenian prince and leader of a rebellion against the Abbasid Caliphate, is captured by the Abbasid army, and brought to the caliphal capital of Samarra.source
• 851Danish Viking raiders enter the Thames Estuary, and plunder Canterbury and London. They land at Wembury near Plymouth, but are defeated by Anglo-Saxon forces led by King Ethelwulf of Wessex. His eldest son Æthelstan of Kent, accompanied by Ealdorman Ealhhere, attacks a Viking fleet off the coast at Sandwich, and captures nine of the enemy vessels while the remainder flees.source
• 852Emperor Lothair I and his (half) brother Charles the Bald join forces to remove the Vikings from the island of Oscelles, in the River Seine. After this fails, Charles again pays them tribute (Danegeld).source
• 852A Viking fleet of 350 vessels enters the Thames Estuary before turning north, and engages the Mercian forces under King Beorhtwulf. The Mercians are defeated, and retreat to their settlements. The Vikings then turn south and cross the river somewhere in Surrey; there they are slaughtered by a West Saxon army, led by King Æthelwulf and his son Aethelbald, at Oak Field (Aclea).source
• 853May 22 – A Byzantine fleet (85 ships and 5,000 men) sacks and destroys the port city of Damietta, located on the Nile Delta in Egypt. A large quantity of weapons and supplies intended for the Emirate of Crete are captured.source
• 853Danish Vikings attempt to subjugate the Curonians on the shoreline of the Baltic Sea, but they are repulsed. King Olof leads Swedish Vikings in retaliation, and attacks the towns of Seeburg and Apuolė (modern Courland).source
• 853King Burgred of Mercia appeals to Æthelwulf, king of the West Saxons, for help against the rebellious Welsh king Rhodri the Great. Æthelwulf agrees to send help, and Wales is subdued as far north as Anglesey.source
• 854Croatian–Bulgarian battle: Bulgarian Khan (later Knyaz) Boris I, attacks the Duchy of Littoral Croatia, ruled by Duke Trpimir I during the First Croatian-Bulgarian War. It is fought on the Croatian territory in the vicinity of the Croatian–Bulgarian border in present-day northeastern Bosnia and Herzegovina. None of the warring sides emerges victorious, Bulgarian forces retreat and finally both parties subsequently conclude a peace treaty.source
• 855Caliph al-Mutawakkil sends an Abbasid army, led by the Turkic general Bugha al-Kabir, to suppress an uprising of rebellious Armenian nakharars. He subdues the country, and deports many Armenian nobles to the caliphal capital of Samarra.source
• 856Winter – Æthelwulf returns to Wessex to face a revolt by his eldest son Æthelbald, who usurps the throne. Æthelwulf agrees to give up the western part of his kingdom, in order to avoid a civil war. He keeps control over Sussex, Surrey, Essex and Kent, over which Prince Æthelberht has presided.source
• 857November – Erispoe, ruler (duke) of Brittany, is assassinated by his cousin Salomon and followers, in the church at Talensac. King Charles the Bald acknowledges Salomon as the rightful 'king' of Brittany.source
• 857Viking chieftain Rorik, with the agreement of King Lothair II, leaves Dorestad with a fleet and forces his rival Horik II to recognise him as ruler over Denmark (approximate date).source
• 858Summer – King Louis the German, summoned by the disaffected Frankish nobles, invades the West Frankish Kingdom and secures Aquitaine for his nephew Pepin II ("the Younger"). King Charles the Bald flees to Burgundy; he is saved by the help of the bishops, and by the fidelity of the family of the Welfs, who are related to Judith (second wife of former emperor Louis the Pious).source
• 859January 15 – Battle of St. Quentin: Frankish forces, led by Humfrid, defeat King Louis the German at Saint-Quentin (Northern France). Humfrid is enfeoffed with the County of Autun, and appointed Margrave of Burgundy, by King Charles the Bald.source
• 859Battle of Albelda: King Ordoño I of Asturias, and his ally García Íñiguez I, defeat the Muslims under Musa ibn Musa al-Qasawi at Albelda.source
• 859Viking raiders invade the Kingdom of Pamplona (Western Pyrenees), and capture King García Íñiguez I, somewhere in the Andalusian heartland. They extort a ransom, rising to around 70,000 gold dinars.source
• 860June 18 – Byzantine–Rus' War: A fleet of about 200 Rus' vessels sails into the Bosphorus, and starts pillaging the suburbs of Constantinople. The raiders set homes on fire, and drown and kill the citizens. Unable to do anything to repel the invaders, Patriarch Photios I urges his flock to implore the Theotokos to save the Byzantine capital. Having devastated the suburbs, the Rus' Vikings pass into the Sea of Marmara and attack the Isles of the Princes, plundering the local monasteries.source
• 860Muhammad I, Umayyad emir of Córdoba, invades Pamplona (Pyrenees), and captures Crown Prince Fortún Garcés in Milagro, along with his daughter Onneca Fortúnez, and takes them as hostages to Córdoba.source
• 860Summer – Viking raiders led by Weland sail to England and attack Winchester (the capital of Wessex), which is set ablaze. He spreads inland, but is defeated by West Saxon forces, who deprive him of all he has gained.source
• 860Summer – The Viking chieftains Hastein and Björn Ironside ravage upstream and move to Italy, sacking Luna (believing it to be Rome). They sail up the River Arno to sack the cities of Pisa and Fiesole (Tuscany).source
• 861March – Robert the Strong is appointed margrave of Neustria by King Charles the Bald. He re-establishes the Breton March, and extends his remit by campaigning against Salomon, duke 'king' of Brittany. Robert hires a combined Seine-Loire fleet for 6,000 pounds of silver, 'before Salomon can ally with them against him'. In return, Salomon enlists 12 Viking ships under the command of Hastein, to raid the county of Maine, which, with Anjou, becomes squeezed between Brittany and Neustria.source
• 861Carloman, eldest son of King Louis the German, revolts against his father. He is captured, but manages to escape to the Ostmark (or 862).source
• 861Ya'qub ibn al-Layth, a Muslim military leader, starts rebelling against the Abbasids and founds the Saffarid Dynasty in the 870s. He rules over parts of Khurasan and eastern Iran, and establishes his capital at Zaranj (modern Afghanistan).source
• 861Summer – Viking raiders sack the cities of Paris, Cologne, Aachen, Worms and Toulouse.source
• 862Carloman, eldest son of King Louis the German, revolts against his father. He is captured, but manages to escape to the Ostmark (or 861).source
• 862First raid of the Hungarians in the Carpathian Basin at the request of Rastislav of Moravia against the East Frankish Kingdom.source
• 862Robert the Strong, margrave of Neustria, captures 12 Viking ships and kills their crews. He pays tribute (Danegeld) for keeping the Vikings out of Neustria.source
• 863September 3 – Battle of Lalakaon: A Byzantine army confronts an invasion by Muslim forces, led by Umar al-Aqta, Emir of Malatya. The Muslims raid deep into Byzantine territory, reaching the Black Sea coast at the port city of Amisos. Petronas annihilates the Arabs near the River Lalakaon, in Paphlagonia (modern Turkey).source
• 863King Osberht of Northumbria engages in a dispute for royal power, with a rival claimant named Ælla. After Osberht is replaced, Ælla wields power in Northumbria, but the civil war continues.source
• 863The Byzantine Empire invades Bulgaria in order to impose Orthodox Christianity on Boris I.source
• 863King Louis the German suppresses the revolt of his son Carloman (for the second time), who wants a partition (mainly of Bavaria) of the East Frankish Kingdom.source
• 864Viking raiders, led by Olaf the White, arrive in Scotland from the Viking settlement of Dublin (Ireland). He rampages the country, until his defeat in battle by King Constantine I.source
• 864Pepin II joins the Vikings in an attack on Toulouse. He is captured while besieging the Frankish city. Pepin is deposed as king of Aquitaine, and imprisoned in Senlis.source
• 864King Louis the German invades Moravia, crossing the Danube River to besiege the civitas Dowina (identified, although not unanimously, with Devín Castle in Slovakia).source
• 864Robert the Strong, margrave of Neustria, attacks the Loire Vikings in a successful campaign. Other Viking raiders plunder the cities of Limoges and Clermont, in Aquitaine.source
• 865The Great Heathen Army (probably no more than 1,000 men) of Vikings, led by Ivar the Boneless and Halfdan Ragnarsson, invades East Anglia. King Edmund of East Anglia buys peace with a supply of horses.source
• 865Boris I, ruler (knyaz) of the Bulgarian Empire, suppresses a revolt, and orders the execution of 52 leading boyars, along with their whole families.source
• 866July 2 – Battle of Brissarthe: Frankish forces, led by Robert the Strong, are defeated by a joint Breton-Viking army.source
• 866The Kharijite revolt against the Abbasid Caliphate begins in Al-Jazira (Upper Mesopotamia), which will last for 30 years.source
• 866Louis II, Holy Roman Emperor, defeats the Saracen invaders who are ravaging southern Italy.source
• 866An army in Lucera is assembled by orders of Louis II in preparation for an attack on the Emirate of Bari.source
• 867Deira, the southernmost part of Northumbria, is conquered by the Vikings. Ivar the Boneless, one of their leaders, installs a puppet king of Northumbria, Ecgberht I.source
• 867The rival monarchs of Northumbria, Ælla and Osberht, join forces in an attempt to expel the Great Heathen Army, but are defeated in battle by Ivar the Boneless and Halfdan Ragnarsson. Osberht is killed in battle, while Ælla is reportedly captured, before being subject to the blood eagle: a combined method of torture and execution.source
• 868King Burgred of Mercia appeals to Æthelred I for help in resisting the Great Heathen Army. The Danes occupy Nottingham, and stay through the winter without any serious opposition.source
• 868Al-Andalus: The city of Mérida rises against the Umayyad rule. Emir Muhammad I regains control, and has the walls of the city destroyed. He supports the rival creation of Badajoz in retaliation.source
• 868Salomon, duke ('king') of Brittany, leads a joint campaign against the Loire Vikings. He is forced to defend southeastern Brittany unaided, and mobilizes levies raised at Poitiers to defeat the Vikings.source
• 868Muslim Arab forces under Muhammad II, emir of the Aghlabid Dynasty (modern Tunisia), conquer the island of Malta and raid into the mainland of Italy.source
• 868King Áed Findliath drives the invading Danes and Norwegians out of Ireland, after defeating them at the Battle of Killineery.source
• 869November 20 – Vikings conquer East Anglia, killing King Edmund the Martyr.source
• 869The Danes, led by Viking chieftain Ivar the Boneless, 'make peace' with the Mercians (by accepting Danegeld). Ivar leaves Nottingham on horseback, and returns to York.source
• 869Summer – Caliph Al-Mu'tazz is murdered by mutinous Muslim troops, after a 3-year reign. He is succeeded by Al-Muhtadi (a grandson of the late Al-Mu'tasim), as ruler of the Abbasid Caliphate.source
• 869The Zanj Rebellion: The Zanj (black slaves from East Africa), provoked by mercilessly harsh labor conditions in salt flats, and on the sugar and cotton plantations of southwestern Persia, revolt.source
• 869Summer – Emperor Basil I allies with the Frankish emperor Louis II against the Saracens. He sends a Byzantine fleet of 400 ships (according to the Annales Bertiniani), under the command of Admiral Niketas Ooryphas, to support Louis (who is besieging the city port of Bari) and to clear the south of the Adriatic Sea of Muslim raiders.source
• 869Autumn –The Great Heathen Army, led by Ivar the Boneless and Ubba, invades the Kingdom of East Anglia and plunders Peterborough. The Vikings take up winter quarters at Thetford.source
• 870December 31 – Battle of Englefield: The Vikings clash with ealdorman Æthelwulf of Berkshire. The invaders are driven back to Reading; many of the Danes (including one of the earls named Sidrac) are killed.source
• 870Autumn – The Great Heathen Army, led by Ivar the Boneless and Ubba, invades East Anglia and plunders Peterborough. King Edmund the Martyr is captured, tortured, beaten and used for archery practice (or 869).source
• 870The Danes, led by Halfdan Ragnarsson and Bagsecg, invade Wessex and take the royal estate at Reading (Berkshire), which Halfdan makes his headquarters. A naval Viking contingent sails up the Thames River.source
• 870The Zanj Rebellion: The Zanj (black slaves from East Africa) capture the Abbasid seaport of Al-Ubullah at the Persian Gulf, and cut off communications with Basra (modern Iraq).source
• 870The Danes, led by Ivar the Boneless and King Olaf of the Dublin Vikings, besiege Dumbarton in Scotland, the capital of King Artgal of Stratchlyde. After a siege of four months, the citadel is captured and destroyed.source
• 871January 4 – Battle of Reading: A West Saxon force, under the command of King Æthelred I and his brother Alfred, is defeated by the Danes at Reading. Among the many dead on both sides is Æthelwulf. The Saxon troops are forced to retreat, allowing the Vikings to continue their advance into Wessex.source
• 871January 8 – Battle of Ashdown: The West Saxons, led by Æthelred I and Alfred, gather at the Berkshire Downs. The Danes under the command of Halfdan and Bagsecg occupy the high ground, but are successfully attacked by Alfred's men. During the battle Alfred breaches the shield wall formation.source
• 871January 22 – Battle of Basing: The West Saxon army, under the command of Æthelred I, is defeated at Basing. The Danes, led by Halfdan, are victorious; Æthelred is forced to flee and regroup, leaving behind precious winter supplies.source
• 871February 2 – Franco-Lombard forces, aided by a Croatian fleet (of Sclaveni), led by Emperor Louis II, capture Bari, capital of the Emirate of Bari in Southern Italy.source
• 871March 22 – Battle of Meretum: The West Saxons, led by Æthelred I and Alfred, are defeated by the Danes. Among the many dead is Heahmund, bishop of Salisbury.source
• 871May – Battle of Wilton: Alfred the Great is defeated by the Danes at Wilton (along the southern side of the River Wylye), leaving him in retreat for several years.source
• 871September – Battle of Basra: Zanj rebels in Mesopotamia sack and capture Basra (see Zanj Rebellion).source
• 871The English retreat onto the Berkshire Downs. The Great Heathen Army, led by the Danish Viking kings Halfdan and Bagsecg, march out after the Saxons. Six pitched battles are fought between the Danes and Wessex. Of two of them the place and date are not recorded, the others are:source
• 872May 18 – After his successful campaign against the Saracens, Louis II is crowned as Roman Emperor ("Emperor of the Franks") for the second time and converts the Muwalladun, and the Arab elite.source
• 87218 July (traditional date) – Battle of Hafrsfjord: Norse chieftain Harald Fairhair wins a great naval victory at Hafrsfjord, outside Stavanger. He becomes (at age 18) the first king of Norway. Harald's conquests and taxation system lead many Viking chiefs and their followers to emigrate to the British Isles, and (later) to Iceland.source
• 872The Zanj Rebellion: The Zanj (black slaves from East Africa) defeat the Abbasid forces, led by caliphal regent Al-Muwaffaq (brother of caliph Al-Mu'tamid). Hostilities in Mesopotamia (Southern Iraq) will preoccupy Al-Muwaffaq, and the Zanj will remain on the offensive over the next several years.source
• 872King Artgal of Strathclyde is slain, through the connivance of King Constantine I of Alba (modern Scotland) and his Viking allies. Artgal's son, Run, succeeds to the Strathclyde throne.source
• 872Autumn – The Great Heathen Army returns to Northumbria, to put down a rebellion at York. King Ecgberht I and his archbishop, Wulfhere, are expelled by the Northumbrians and flee to Mercia.source
• 873The Danish Great Heathen Army, led by the Viking leaders Halfdan and Guthrum, attack Mercia and capture the royal centre at Repton (Derbyshire). The Vikings establish an encampment with a U-shape ditch, on the south bank of the River Trent and spend the winter there.source
• 873Al-Andalus: The city of Toledo (modern Spain) rises up for a second time against Umayyad rule, due to ethnic tensions over two years.source
• 873Muhammad ibn Tahir, Muslim governor of Khorasan, is overthrown by the Saffarids, led by Ya'qub ibn al-Layth, who conquer the capital, Nishapur. Khorasan is annexed to their own empire in eastern Persia. The Tahirid Dynasty falls.source
• 874Huang Chao, a salt privateer, joins forces with Wang Xianzhi to raise a rebel army at Changyuan (modern Xinxiang). The uprising further weakens the Tang dynasty, which is already weakened by natural disasters such as severe droughts and floods.source
• 874Autumn – The Great Heathen Army splits into two bands; Halfdan returns with his forces to Northumbria, along with his brother Ubba, where he establishes a new base on the River Tyne.source
• 874The Danish Vikings (from their base at Repton) drive King Burgred of Mercia into exile, and sack Tamworth. They conquer his kingdom and install his political opponent, Ceolwulf II, as sub-king.source
• 875June – The Great Heathen Army, led by Guthrum, moves on Cambridge. He later returns to Wessex, to establish a winter quarter. King Alfred the Great fights the Danes in a naval engagement.source
• 875Danish Vikings, probably led by Halfdan Ragnarsson, invade Dublin. During the fighting, Eystein Olafsson, king of Dublin, is killed.source
• 875Battle of Dollar: Invading Danish Vikings defeat the Scots and the Picts, under King Constantine I, at Dollar. They occupy Caithness, Sutherland, Ross and Moray, far to the north.source
• 876April 8 – Battle of Dayr al-'Aqul: Abbasid forces, led by Al-Muwaffaq, halt a Saffarid invasion on the River Tigris. Emir Ya'qub ibn al-Layth tries to capture the Abbasid Caliphate's capital of Baghdad, but he is forced, with his army, to retreat.source
• 876October 8 – Battle of Andernach: Frankish forces, led by Louis the Younger, prevent a West Frankish invasion and defeat Charles II at Andernach. The Rhineland remains part of the East Frankish Kingdom.source
• 876The Great Heathen Army, led by Guthrum, captures the fortress of Wareham (Dorset), and is met by a Viking army (3,500 men) from the sea, which lands at Poole Harbour. King Alfred the Great traps the Vikings, and demands hostages in return for a peace agreement. The Danes divide their forces; half flees to Exeter, where they besiege the town while the other half escape in their ships, but are lost in a storm near Swanage.source
• 877August – Siege of Syracuse: The Aghlabids begin raiding the Byzantine territories, in the east of the island of Sicily. They besiege Syracuse, and blockade the fortress city by sea and land.source
• 877King Constantin I is killed fighting Viking raiders, at the "Black Cave" in Fife. He is succeeded by his brother Áed mac Cináeda as ruler of Alba (Scotland).source
• 877The Vikings invade Wales once more, and King Rhodri ap Merfyn ("the Great") of Gwynedd, Powys and Seisyllwg is forced to flee to Ireland (approximate date).source
• 877Autumn – King Alfred the Great raises a large force, and marches on the Viking camp at the city of Exeter. His army besieges the Great Summer Army, led by Guthrum, and forces the Vikings to surrender. They flee north to Gloucester, and settle in the Five Boroughs (modern East Midlands).source
• 877Battle of Strangford Lough: King Halfdan I leaves for Ireland, in an attempt to claim the Kingdom of Dublin from his rival Bárid mac Ímair. He is killed in battle at Strangford Lough, and a probable interregnum follows in York.source
• 878January 6 – Battle of Chippenham: King Alfred the Great of Wessex is surprised by a Viking attack at Chippenham in Wiltshire. He is forced to flee, with his retinue, into the Somerset Levels for safety. From his headquarters at Athelney, Alfred wages guerrilla warfare against the Vikings.source
• 878March–April – Wilfred the Hairy (ruler of the Catalan counties) with other supporters of Louis the Stammerer (King of West Francia) defeat noble supporters of the rebel Bernard of Gothia.source
• 878May 21 – Siege of Syracuse: The Aghlabids capture the Byzantine fortress city of Syracuse, after a nine-month siege. Most of the population is massacred by the Arabs.source
• 878May – Battle of Edington: Supported by all the levies of Somerset, Wiltshire and Hampshire, Alfred the Great decisively defeats the main body of Danish Vikings, led by King Guthrum, at modern-day Edington, Wiltshire (near Bratton Castle).source
• 878Battle of Cynwit: Viking raiders, led by Ubba Ragnarsson, land on the coast at Combwich with 23 ships, and besiege a hillfort (called Cynwit) at Cannington, Somerset. Ealdorman Odda launches a surprise attack, and kills Ubba in battle.source
• 878King Rhodri the Great of Gwynedd, Powys and Seisyllwg, returns to his kingdoms, but is killed fighting the Mercians of King Ceolwulf II. His kingdoms are divided amongst his three sons: Anarawd, Merfyn and Cadell.source
• 878King Áed mac Cináeda of Scotland is killed in battle, by his rival Giric mac Dúngal. Giric becomes king of the Picts, and allies himself with Eochaid (grandson of Kenneth I). The two rule all of Alba (Scotland) together as joint-kings.source
• 878Reconquista: King Alfonso III of Asturias conquers the city of Coimbra (modern Portugal), which is under the Umayyad Caliphate.source
• 878Zanj Rebellion: The Zanj (black slaves from East Africa) in Mesopotamia seize Wasit (modern Iraq), and establish a presence in the Persian province of Khuzestan.source
• 879Guangzhou Massacre: The Chinese rebel leader Huang Chao besieges the seaport in Guangzhou, and slaughters many of its inhabitants and foreign merchants. According to sources, the death toll ranges from 120,000 to 200,000 foreigners.source
• 879Zanj Rebellion: The Abbasid Caliphate concentrates its efforts against the Zanj rebels in Mesopotamia. The Abbasid general Al-Mu'tadid leads an expeditionary force (10,000 men) to suppress the revolt. This marks the turning-point of the war.source
• 879Oleg, brother-in-law of the Varangian ruler Rurik, is entrusted to take care of his kingdom Novgorod after his death. He becomes regent of his son Igor.source
• 879Viking leader Guthrum becomes 'king' of East Anglia. A Viking fleet sails up the River Thames, and builds a camp at Fulham (near London) to prepare for an invasion of France.source
• 880February 2 – Battle of Lüneburg Heath: King Louis III is defeated by the Norse Great Heathen Army at Lüneburg Heath. The Saxons are routed in a snowstorm; many drown in the river or are captured during the retreat.source
• 880December 22 – Luoyang, eastern Chinese capital of the Tang dynasty, is captured by rebel leader Huang Chao, during the reign of emperor Xizong.source
• 880Battle of Cephalonia: A Byzantine fleet, under Admiral Nasar, is sent by Emperor Basil I to the Ionian Islands. Nasar defeats the Aghlabids in a night battle near Cephalonia (modern Greece).source
• 880Battle of Fjaler: King Harald Fairhair moves east along the Norwegian coast with his fleet. He defeats his rival Atle Mjove at Fjaler in Sunnfjord, and lands with his longships at Tønsberg.source
• 880Battle of Thimeon: King Louis III ("the Younger") defeats Vikings (probably Norsemen) from England, near Charleroi, north of the River Sambre. During the battle 5,000 Vikings are killed.source
• 881August 3 – Battle of Saucourt-en-Vimeu: The West Frankish kings Louis III, and his brother Carloman II, rout Viking raiders (near Abbeville).source
• 881Anarawd, and his brothers Cadell and Merfyn, begin extensive military campaigns to quell resistance in Powys and Seisyllwg (approximate date).source
• 881Battle of the Conwy: King Anarawd of Gwynedd (Wales) initiates a revenge attack on the Mercian armies, and defeats them on the River Conwy.source
• 881Zanj Rebellion: Abbasid general Al-Muwaffaq lays siege to the Zanj capital of Mukhtara, using his base on the opposite side of the River Tigris.source
• 882April 11 – Battle of Remich: A Frankish army under Bishop Wala of Metz is defeated by Vikings, who are on a raid, near Remich (modern Luxembourg). During the fighting Wala is killed.source
• 882Oleg of Novgorod takes Kiev, and makes it his capital, forming the Kievan Rus'.source
• 882King Alfred the Great increases the size of his new navy, and sails out to attack four Viking ships. Two of the ships are captured (before they surrender), and the other crews are killed.source
• 882Siege of Asselt: Charles the Fat besieges a Viking camp, who have plundered along the Meuse, the Rhine and the Moselle. He defeats their leader Godfrid, and grants him West Frisia.source
• 883September 11 – Yazaman al-Khadim, Abbasid governor of Tarsus, routs a Byzantine army under general Kesta Styppiotes, in a night attack. According to Arab chroniclers, 70,000 out of 100,000 Byzantine troops are killed.source
• 883The Zanj Rebellion: Abbasid general Al-Muwaffaq brings in Egyptian forces, to help him in his two-year siege of the Zanj capital Mukhtara. He captures the city, and crushes the revolt that has devastated Chaldea (modern Iraq) since 869.source
• 883King Charles the Fat travels to Nonantola (Northern Italy), where he meets Pope Marinus I. He receives complaints of Guy II of Spoleto, who is the official "protector" of Rome, and invades the Papal States. King Charles orders Guy to appear before a tribunal.source
• 884The Huang Chao rebellion is suppressed by forces of Emperor Xi Zong, with the help of the Shatuo Turks. Chinese warlords rule the country, instead of the imperial government.source
• 884Summer – King Carloman II reverts to the former fall-back of 'pay and pray', buying (with Danegeld) a truce at Amiens, while he raises 12,000 lbs of silver for the Vikings to depart.source
• 885November 25 – Siege of Paris: Viking forces, under the Norse chieftains Sigfred and Sinric, sail up the River Seine for eastern France, with a fleet of 300 longships (10,000 men). They appear before Paris, and offer to spare the city if they are allowed free passage, by paying them tribute (Danegeld). Their request is denied.source
• 885November 27 – The Vikings begin the Siege of Paris by attacking the northeast tower with ballistae, mangonels and catapults. All Viking attacks are repulsed by Count Odo, who defends the city with a small garrison (about 200 men). Sigfred decides to withdraw, and builds a camp on the right bank of the river. Meanwhile he mines the city, and scours the countryside for provisions.source
• 885Danish Vikings land in Kent and besiege Rochester. Town defences having been improved, the city holds out long enough for Alfred the Great to organize an army. He forces the Vikings to flee back across the Channel, to the Continent.source
• 885Battle of Tawahin: Muslim forces (4,000 men) of the Abbasid Caliphate, under Al-Mu'tadid, are defeated near Ramlah (modern Israel) by Khumarawayh, ruler of the Tulunid dynasty. This ends the Abbasid attempt to recover Syria from the Tulunids. A large part of the Abbasid army is captured, and transported to Egypt. Khumarawayh aims for reconciliation with the caliphal government, and allows the soldiers who want to return to modern-day Iraq to depart without ransom, while offering the rest the opportunity to settle in Egypt.source
• 885Kings Hyfaidd of Dyfed, Elisedd of Brycheiniog and Hywel of Glywysing, being harassed by the armies of King Anarawd in Wales, seek the protection of Alfred the Great, and submit to his overlordship. Anarawd seeks an alliance with King Guthred of York.source
• 885A naval force raised by Alfred the Great takes part in the two Battles of the River Stour.source
• 886October – Siege of Paris: Count Odo slips through Viking-controlled territory, to ask the king of West Francia Charles the Fat for support. He returns with a relief force, and reaches safety within the walls. Charles arrives later with a large army, and establishes a camp at Montmartre. After negotiations he promises the Vikings tribute (Danegeld) worth 700 Livres (equivalent to 257kg of silver), and allows them to sail up the River Seine, to over-winter in Burgundy.source
• 887November 17 – East Frankish magnates revolt against the inept emperor Charles III (the Fat) in an assembly at Frankfurt, and depose him. His nephew Arnulf of Carinthia, the illegitimate son of former king Carloman of Bavaria, is elected ruler of the East Frankish Kingdom. Charles yields his throne without a struggle, and retires to Neidingen.source
• 887The city of Toledo rises against the Umayyad Dynasty, in Al-Andalus (modern Spain).source
• 888October – Alan I (the Great), count of Vannes, and his rival Judicael, unite their forces to defeat the Vikings at Questembert (or 889). Judicael is killed, in a notable victory for the Bretons, with 15,000 Vikings crushed, some few 400 escaping to their ships. In command of a 'united' Breton force, Alan is able to drive the Vikings back to the Loire River. Alan becomes sole ruler of Brittany, and over the Frankish counties of Rennes, Nantes, Coutances and Avranches.source
• 888October – Battle of Milazzo: The Aghlabids score a crushing victory over a Byzantine fleet off Sicily.source
• 889Lord Æthelred II and Lady Æthelflæd (a daughter of king Alfred the Great) of the Mercians begin their policy of fortifying Mercian cities as defensive burghs, starting with Worcester (approximate date).source
• 889Kings Eochaid and Giric of Alba and Strathclyde (modern Scotland) are deposed by Viking invaders. They are succeeded by Donald II, the son of the late Constantine I, who becomes king of Scotland.source
• 889The Unified Silla kingdom (modern Korea) under King Jinseong seeks to collect taxes by force from peasants, setting off massive peasant rebellions (approximate date).source
• 889The Magyars, an Ugric tribe from the steppe of Central Asia, move west under the leadership of Árpád. They are pushed by their rivals, the Pechenegs, into the Balkan Peninsula, and become entangled in a war between Bulgaria and the Byzantine Empire. The Magyars head north and settle in Great Moravia.source
• 890In March or April 890, the ambitious warlord Zhu Quanzhong (later called Zhu Wen) faced a mutiny at Suzhou and was unable to retake the city. He pressured Emperor Zhaozong of Tang China to launch a campaign against his primary rival, Li Keyong. By winter 890, Zhu strategically shifted his focus northward, giving up his claim to the Huainan Circuit after failing to take it.source
• 891Summer – Orso, Lombard prince of Benevento, is deposed after the capture of Benevento by the Byzantines. Benevento becomes the capital of the thema of Longobardia.source
• 891Battle of Leuven: Viking raiders on the Dyle River (near Leuven), in modern-day Belgium, suffer a crushing defeat by Frankish forces under King Arnulf of Carinthia.source
• 891Muslim forces led by Abdullah ibn Muhammad al-Umawi, Umayyad emir of Córdoba, defeat the rebel leader Umar ibn Hafsun at Poley, in Al-Andalus (modern Spain).source
• 892May – Ibrahim II, Aghlabid emir of Ifriqiya, sends a large army to Palermo, to impose Arab authority from Kairouan. After an uprising, the Sicilians make a bid for independence.source
• 892Autumn – A Viking force with a fleet of 250 longships arrives at the river mouth of the settlement of Lympne (East Kent). They attack the small fortification (called Eorpeburnan).source
• 892Viking raiders (80 ships) under Hastein arrive in the Thames Estuary, and set up camp at Middleton. King Alfred the Great decides to position his army in the Wealden Forest.source
• 892Summer – Poppo II, duke of Thuringia (Central Germany), is deposed by King Arnulf of Carinthia. East Frankish forces and their Magyar (Hungarian) allies invade Great Moravia.source
• 892Bagratid Armenia conquers Dwin City from the Arabs.source
• 892Former Silla general Kyŏn Hwŏn seizes the cities of Wansanju and Mujinju, taking over the territory of Baekje. He wins the support of the people, and declares himself king.source
• 893An East Frankish expeditionary force under Zwentibold, the eldest son of King Arnulf of Carinthia, crosses the Alps into Friuli. He makes junction at Verona, with the army of the deposed king Berengar I, and proceeds to lay siege to Pavia. After a three-month campaign, Zwentibold receives orders to head back to Bavaria, in case of a Magyar intervention.source
• 893Vladimir, ruler (khan) of the Bulgarian Empire, is dethroned by his father Boris I, with help from loyal boyars. He is blinded, and succeeded by his brother Simeon I, as prince of Bulgaria; the capital is moved from Pliska to Preslav. Simeon makes an alliance with the Pechenegs (or Patzinaks), a semi-nomad Turkic tribe from the Central Asian steppes.source
• 893Autumn – Danish Vikings under Hastein take the city of Chester, after a rapid march from East Anglia. Alfred the Great destroys the food supplies, forcing them to move into Wales.source
• 893Summer – Battle of Buttington: A combined Welsh and Mercian army under Lord Æthelred besieges a Viking camp at Buttington in Wales. The Danes escape with heavy losses, and take their families to safety in East Anglia.source
• 893Spring – A Viking army under Hastein moves to a fortified camp at Benfleet (Essex). The Danish camp is captured by the Saxons, while the army is out raiding. Hastein is forced to retreat to Shoebury.source
• 893Spring – Prince Edward, the son of King Alfred the Great, defeats the Danish Viking raiders at Farnham, and forces them to take refuge on Thorney Island. At the same time, Danes from East Anglia sail around the Cornish coast, and besiege Exeter.source
• 894March – Arnulf of Carinthia proceeds to Piacenza, and from there invades central Italy. After a successful campaign, he calls the invasion off and returns to Pavia – probably because Duke Rudolph I of Burgundy was threatening to invade Lorraine. Arnulf has himself proclaimed King of Italy at Pavia, leaving Berengar I as his vice-regent in Italy.source
• 894The Vikings in Northumbria and East Anglia swear allegiance and hand over hostages to King Alfred the Great, but promptly break their truce by attacking the southwest of England. A Viking force returns from Exeter and sails along the coast, in an attempt to plunder Chichester. They are defeated by the Saxon garrison, losing many ships and men.source
• 894Prince Petar of Serbia defeats his revolting cousin Bran; he is captured and blinded (according to a Byzantine tradition that meant to disqualify a person from taking the throne).source
• 894Spring – King Arnulf of Carinthia invades Italy at the head of an East Frankish expeditionary army, joining up with the deposed king Berengar I at Verona. He conquers Brescia after little resistance, and sacks Bergamo after a one-month siege. The cities of Milan and Pavia open their doors to Arnulf. Emperor Guy III escapes from Pavia, to hide in the mountains of Spoleto (Umbria).source
• 894King Anarawd of Gwynedd's shaky alliance with the Vikings collapses. His kingdom is ravaged by the Norsemen. Anarawd is forced to ask for help from Alfred the Great and submits to his overlordship. Alfred imposes oppressive terms and forces Anarawd's confirmation in the Christian Church, with Alfred as 'godfather'.source
• 894Árpád, head of the confederation of the Hungarian tribes, comes to an agreement with the prince of the Moravians, Svatopluk II, that Hungarian and Moravian armies will together expel the Eastern Franks from Pannonia.source
• 894Arnulf of Carinthia returns to Germany through the Alps, harried by militias dispatched by Rudolph I of Burgundy and margrave Anscar I of Ivrea. Only with much difficulty is Arnulf able to get his army through the Aosta Valley and through St. Moritz, back into Germany. Guy III descends from the Apennines, and re-seizes the Italian kingdom.source
• 894Byzantine–Bulgarian War: Stylianos Zaoutzes, leading minister and basileopator, convinces Emperor Leo VI (the Wise) to move the Bulgarian market from Constantinople to Thessaloniki. This affects the commercial importance of Bulgarian trade. Simeon I, ruler (khan) of the Bulgarian Empire, mobilizes his Bulgarian forces and invades Byzantine territory, ravaging the countryside.source
• 894Autumn – Battle of Benfleet: Danish Viking forces retire to Essex, after being deprived of food by Alfred the Great (see 893). They draw their longships up the Thames and into the Lea, entrenching themselves at Benfleet.source
• 895December – Arnulf of Carinthia invades Italy, at the head of an East Frankish expeditionary army. He arrives in Pavia and reorganizes the Lombard state. Arnulf partitions the northern part of the kingdom: the western half (March of Lombardy) and the eastern half (March of Verona).source
• 895The Magyars are expelled from western Siberia, and settle in the Carpathian Basin, under the leadership of Árpád (the traditional date of 896 held during the 20th century has proved to be erroneous). Emperor Leo VI (the Wise) seeks aid from the Magyars, and after crossing the Danube on Byzantine ships, they ravage Bulgarian territory.source
• 895King Anarawd of Gwynedd is supplied with English troops, to assist in his reconquest of Seisyllwg (Wales). He is successful, and his brother Cadell is finally able to take his rightful place on the Seisyllwg throne.source
• 895Arnulf of Carinthia crosses the Po River and divides his army in two: one corps (Swabian) proceeds to Florence (via Bologna), while the other corps (Franks) moves through the Lunigiana to the precincts of Rome.source
• 895Spytihněv I, duke of Bohemia, together with the Slavník prince Witizla, breaks away from Great Moravia, and swears allegiance to Arnulf of Carinthia in Regensburg.source
• 895King Odo (or Eudes) takes a large army against Rheims, and forces anti-king Charles the Simple to flee to Germany. King Arnulf of Carinthia, throwing off his agreements with Odo, charges his illegitimate son Zwentibold to invade the West Frankish Kingdom, and re-install Charles on the throne.source
• 895Guy IV, duke of Spoleto, conquers Benevento (after the Byzantines have moved the capital of Byzantine Italy from Benevento to Bari). Guy makes himself prince, thereby uniting the two Italian states. The Byzantines attempt to retake Benevento, but are defeated by Lombard troops.source
• 895Simeon I (the Great), ruler (khan) of the Bulgarian Empire, seeks refuge in the fortress of Drastar, while the Magyars reach the outskirts of the capital Preslav. Facing a difficult situation with war on two fronts, Simeon calls for a truce. Leo VI sends the diplomat Leo Choirosphaktes to Bulgaria, to negotiate the terms.source
• 896February – King Arnulf of Carinthia invades Italy at the head of an East Frankish expeditionary army. He storms Rome (the Leonine City), and has himself crowned Holy Roman Emperor by Pope Formosus at St. Peter's. Arnulf sets out to establish his authority in Spoleto, but suffers a stroke; he is forced to call off the campaign, and returns to Bavaria.source
• 896Summer – Battle of Boulgarophygon: Simeon I invades the Theme of Thrace (in the southeastern Balkans). The Byzantines transfer a new army to Europe, to deal with the Bulgarian threat. The armies clash at Boulgarophygon (modern Turkey); the Byzantines are completely destroyed in battle.source
• 896Prince Klonimir, pretender to the throne of the Serbian Principality, is defeated by his ruling cousin, Petar. He is recognized as sole ruler of Serbia by Simeon I, resulting in a 20-year peace and alliance (approximate date).source
• 896A Viking pirate army under Hastein (a son of Ragnar Lodbrok) ravages the Welsh kingdoms of Brycheiniog and Gwent (approximate date).source
• 896Kharijite Rebellion: The Kharijite uprising against the Abbasid Caliphate in Jazira is ended. Caliph Al-Mu'tadid reunifies the entire province under central government, and installs his son and heir, Al-Muktafi, as governor.source
• 896Emperor Zhao Zong appoints Li Keyong, a Shatuo military governor (jiedushi), as Prince of Jin. He becomes the first ruler of Jin (see 907) following the collapse of the Tang dynasty.source
• 896Battle of Southern Buh: Bulgarian forces under Simeon I ('the Great') defeat the Magyars, near the banks of the Southern Buh river (modern Ukraine). The Magyars withdraw from Bulgaria, and are forced to migrate to new pastures. Led by Árpád, they settle in the Carpathian Basin (modern Hungary).source
• 898Summer – Adalbert II, margrave of Tuscany, revolts (pushed by his wife Bertha) against his cousin, Emperor Lambert II. The Tuscan army proceeds against the Lombard capital of Pavia. Lambert with his forces at Marengo defeats Adalbert at Borgo San Donnino, taking him, as a prisoner, to Pavia.source
• 899Muhammad ibn Ahmad al-Shaybani, Muslim ruler of Diyar Bakr, surrenders at the besieged capital of Amid (modern Turkey) to Caliph Al-Mu'tadid in exchange for clemency. Al-Muktafi, the son of Al-Mu'tadid, is installed as governor of the Jazira (Upper Mesopotamia), ending the semi-independent Shaybanid Dynasty, which has ruled in Diyar Bakr since the 870s.source