Geopolitics & Diplomacy in the 9th century

93 sourced entries, 800 CE to 897 CE, oldest first. Also see Geopolitics & Diplomacy across every century or everything else in the 9th century.

• 800June 28 – Ochk'in Kaloomte' Aj Ho' Baak becomes the new ruler of the Mayan city state of Machaquila in Guatemala and reigns until his death in 815.source
• 800The Rus' Khaganate is created by people who are called Rus', after the 182-year dominance of the Khazars. This is the starting period of the rise of the Kievan Rus', and the later states of Russia, Belarus and Ukraine (approximate date).source
• 802May 1 – Lachan Kʼawiil Ajaw Bot (born June 25, 760) becomes the ruler of the Mayan city state near Itzan in Guatemala.source
• 802Prince Jayavarman declares the Khmer Empire (modern-day Cambodia) independent, and establishes the kingdom of Angkor. He is reconsecrated as a world ruler (chakravartin), or god-king (devaraja), under Hindu rites.source
• 802Krum becomes ruler (khan) of the Bulgarian Empire (until 814). During his reign Bulgarian territory doubles in size, from the Danube to the Dniester.source
• 803Emperors Nikephoros I and Charlemagne settle their imperial boundaries in the Adriatic Sea, and sign the Pax Nicephori ("Peace of Nikephoros"). The Byzantines retain control of the coastal cities and islands in Dalmatian Croatia, while Frankish rule is accepted over Istria and the Dalmatian hinterland. Venice is recognized as independent by the Byzantine Empire.source
• 806Emperor Charlemagne divides the Frankish Empire under his three sons, called Divisio Regnorum. For Charles the Younger he designates the imperial title, Austrasia and Neustria, Saxony, Burgundy, and Thuringia. To Pepin he gives Italy, Bavaria, and Swabia. His youngest son Louis the Pious receives Aquitaine, the Spanish March, and Provence.source
• 807The Vikings land on the Cornish coast, and form an alliance with the Cornish to fight against Wessex.source
• 807Dappula II becomes king of Sri Lanka, and makes Anuradhapura the capital city.source
• 808King Godfred of the Danes forms an alliance with the Wiltzi and other Wendic tribes, against the pagan but pro-Frankish Abodrites. Godfred builds earthworks (Danevirke) across the isthmus of Schleswig-Holstein, separating Jutland from the northern extent of the Frankish Empire.source
• 809Aznar Galíndez I succeeds Aureolus, as count of Aragon (modern Spain). He is installed by King Louis the Pious (a son of emperor Charlemagne), and remains a Frankish vassal.source
• 809Emperor Heizei becomes ill, and abdicates the throne in favor of his brother Saga, who is installed as the 52nd emperor of Japan.source
• 810King Godfred of the Danes leads 200 Viking ships to plunder the Frisian coast, and forces the merchants to pay 100 pounds of silver. He claims Northern Frisia as Danish territory.source
• 811Treaty of Heiligen: King Hemming of Denmark concludes a peace treaty with Emperor Charlemagne in present-day Rendsburg. The southern boundary of Denmark is established at the Eider River.source
• 812The Chinese government takes over the issuing of paper bank drafts, the ancestor of paper money.source
• 812Charlemagne conquers Catalonia, as far south as the River Ebro and the Balearic Islands. The counties come under the rule of Bera, count of Barcelona. He signs a three-year peace treaty with the Emirate of Córdoba.source
• 812Emperor Michael I re-opens peace negotiations with the Franks, and recognizes Charlemagne as emperor (basileus) of the Frankish Empire. In exchange for this recognition, Venice is returned to the Byzantine Empire.source
• 813September 11 — Louis the Pious, king of Aquitaine (and only surviving legitimate son), is crowned co-emperor of the Franks, with his father Charlemagne.source
• 813Ashot I ("the Great") becomes the first Georgian Bagratid prince of Iberia, under Byzantine protection.source
• 815Emperor Saga of Japan is the first sovereign to drink tea (according to legend), imported from China by monks. The upper classes adopt this beverage for medicinal use.source
• 815Byzantine–Bulgarian Treaty: Emperor Leo V the Armenian signs a 30-year peace agreement in Constantinople with Omurtag, ruler (khan) of the Bulgarian Empire. The Rhodope Mountains become the Byzantine border again, and Leo regains its lost Black Sea cities, after the Bulgars have them demolished.source
• 815King Egbert of Wessex ravages the territories of the remaining British kingdom Dumnonia, known as the West Welsh (Cornwall).source
• 817Summer – Emperor Louis I issues an Ordinatio Imperii, an imperial decree that lays out plans for an orderly succession. He divides the Frankish Empire among his three sons: Lothair, the eldest, is proclaimed co-emperor in Aachen, and becomes the overlord of his brothers. He receives the dominion of Burgundy (including German and Gallic parts). Pepin, the second son, is proclaimed king of Aquitaine, and receives Gascony (including the marche around Toulouse and parts of Septimania); Louis (the youngest son) is proclaimed king of Bavaria, and receives the dominions of East Francia.source
• 818Beginning of the Lemro period: The Sambawa and Pyinsa Kingdoms are founded in present-day Myanmar.source
• 820Fedelmid mac Crimthainn assumes the kingship as ruler of Munster (modern Ireland).source
• 823May 30 – Emperor Saga abdicates the throne, after a 10-year reign. He is succeeded by his brother Junna, as the 53rd emperor of Japan.source
• 824Iñigo Arista revolts against the Frankish Empire, and establishes the Kingdom of Pamplona, with the support of the Caliphate of Córdoba.source
• 826King Harald Klak of Denmark receives the Frisian county of Rüstringen, as a gift from Emperor Louis the Pious.source
• 828The occupation of Pueblo Bonito (present-day New Mexico) begins.source
• 829Emperor Louis the Pious appoints his 6-year-old son Charles (by his second wife Judith) as ruler of the Frankish subkingdom Alamannia, enraging his eldest son and co-emperor Lothair I, who begins an insurrection.source
• 829Viking chieftain Halfdan the Black becomes king of Agder (modern Norway). He expands his realm through military conquest and political negotiations, dividing the kingdom of Vestfold with his half-brother Olaf.source
• 830King Wiglaf of Mercia regains control from Wessex, and returns to the throne.source
• 831Emperor Louis the Pious is reinstated as sole ruler of the Frankish Empire. He promises his sons Pepin I and Louis the German a greater share of the inheritance. His eldest son Lothair I is pardoned, but disgraced and banished to Italy.source
• 833Mojmir I, Moravian duke, expels Prince Pribina from his homeland (western part of modern Slovakia). He unifies Great Moravia and becomes the first known ruler of the Moravian Slavs, who founds the House of Mojmir (approximate date).source
• 833Emperor Junna abdicates the throne, after a 10-year reign. He is succeeded by his nephew Nimmyō, as the 54th emperor of Japan.source
• 834March 1 – Emperor Louis the Pious is restored as sole ruler of the Frankish Empire. After his re-accession to the throne, his eldest son Lothair I flees to Burgundy.source
• 835Ragnar Lodbrok, a Norse Viking ruler, rises to power. He becomes the scourge of France and England (approximate date).source
• 842February 14 – Oaths of Strasbourg: King Louis the German, ruler of East Francia, and his half-brother Charles the Bald, ruler of West Francia, meet with their armies at Strasbourg. They agree to swear allegiance (recorded in vernacular languages) to each other, and to support each other against their brother Lothair I (nominal emperor of all the Frankish kingdoms and the Holy Roman Empire).source
• 843King Kenneth MacAlpin (Cináed mac Ailpín) of the Scots also becomes king of the Picts; he is crowned (on the Stone of Destiny) as first monarch of the new nation of Scotland. The Alpin Dynasty of Scottish kings begins to reign.source
• 846Prince Pribina becomes a vassal of the Frankish Empire. King Louis the German grants him land near Lake Balaton (modern Hungary). He establishes Blatnohrad, capital of Balaton Principality.source
• 846Máel Sechnaill mac Máele Ruanaid becomes the first High King of Ireland. [Factually disputed. Source needed]source
• 848Emperor Lothair I, and his (half) brothers Louis the German and Charles the Bald, meet in Koblenz to continue the system of "con-fraternal government".source
• 848The Medieval Cholas in Southern India start to rule (approximate date).source
• 848Frankish forces under Count (comté) William of Septimania assume authority over the counties of Barcelona and Empúries (modern Spain).source
• 851Treaty of Angers: Charles the Bald meets Erispoe in Angers, and acknowledges him as "king of Brittany". He recognizes the authority of Breton rule over the areas around Nantes, Rennes and Pays de Retz, which become part of the Breton March, a border zone. Erispoe takes the oath to Charles as king of the West Frankish Kingdom (but not an hommage lige which would be an allegiance). To mark the sovereignty of the Breton state, the future Dukes of Brittany are crowned as "Duke, king in their lands".source
• 851Emperor Lothair I meets with his (half) brothers Louis the German and Charles the Bald in Meerssen (modern-day Netherlands), to continue the system of "con-fraternal government".source
• 852March 4 – Trpimir I, duke (knez) of Croatia, and founder of the Trpimirović dynasty, issues a first state document in Bijaći of all Slavonic peoples. In this Latin document Trpimir refers to himself as the "duke of the Croats" (dux Chroatorum), and to his country as the "state of the Croats" (regnum Chroatorum).source
• 853King Charles the Bald bribes Boris I, ruler (khan) of the Bulgarian Empire, to form an alliance against his brother Louis the German, with Rastislav of Moravia.source
• 854Emperor Lothair I meets his (half) brothers (Louis the German and Charles the Bald) in Attigny, Ardennes for the third time, to continue the system of "con-fraternal government".source
• 856King Charles the Bald cedes the county of Maine to Erispoe, ruler (duke) of Brittany—this in return for an alliance against the Vikings.source
• 862Fan Chuo finishes his Manchu ("Book of the Southern Tribes"), during the Tang Dynasty.source
• 864July 25 – Edict of Pistres: King Charles the Bald orders defensive measures against the Vikings. He creates a large force of cavalry, which inspires the beginning of French chivalry.source
• 864Hasan ibn Zayd establishes the Zaydid Dynasty, and is recognized as ruler of Tabaristan (Northern Iran).source
• 864King Alfonso III conquers Porto from the Emirate of Cordoba. This is the end of the direct Muslim domination of the Douro region.source
• 865King Louis the German divides the East Frankish Kingdom among his three sons. Carloman receives Bavaria (with more lands along the Inn River). He gives Saxony to Louis the Younger (with Franconia, and Thuringia) and Swabia (with Raetia) to Charles the Fat. Louis arranges marriages into the local aristocracy, for his sons to hold important territories along the frontiers.source
• 866Fujiwara no Yoshifusa becomes regent (sesshō) to assist the child emperor Seiwa, starting the Fujiwara regency.source
• 866Boris I, ruler (knyaz) of the Bulgarian Empire, sends a diplomatic mission, led by the Bulgarian nobleman Peter, to Rome, in an effort to renew ties with the West.source
• 867August – Treaty of Compiègne: King Charles the Bald cedes the Cotentin Peninsula to Salomon, duke ('king') of Brittany, after he had sent his son-in-law Pascweten to negotiate a peace. Charles orders the fortification of the cities of Tours, Le Mans and Compiègne.source
• 867Bořivoj I declares himself duke (knyaz) of Bohemia, and founds the Přemyslid Dynasty (approximate date).source
• 868The County of Portugal is established around the town of Portus Cale (present-day Porto) by Vímara Peres, an Asturian nobleman, after the reconquest from the Moors of the region north of the Douro River.source
• 868King Charles the Bald meets his brother Louis the German at Metz. They agree to a partition of Lotharingia, which belonged to former emperor Lothair I (now in possession of his sons Lothair II and Louis II).source
• 868Alfred the Great marries Ealhswith (a daughter of Æthelred, known as Mucel, an ealdorman of the Gaini). He supports his brother Æthelred I, in his choice to form an alliance with Mercia.source
• 870August 8 – Treaty of Meerssen: King Louis the German forces his half-brother Charles the Bald to accept a peace treaty, which partitions the Middle Frankish Kingdom into two larger east and west divisions. Louis receives most of Austrasia (which evolves into the Kingdom of Germany), and Charles receives territory in Lower Burgundy (which evolves into the Kingdom of France). However, large parts of the Frisian coast are under Viking control.source
• 870Wilfred the Hairy, a Frankish nobleman, becomes count of Urgell and Cerdanya (modern-day Catalonia).source
• 870Byzantine–Arab War: A Muslim expeditionary force, led by Halaf al-Hadim, Arab governor of Sicily, conquers Malta. He is welcomed by the local Christian inhabitants as liberator of the agonizing Byzantine yoke. The Muslims sign a treaty with the Christians to live in peace after liberating the island from the Byzantines.source
• 871April 23 – Alfred succeeds as king of Wessex after Æthelred's death. He makes peace with the Danes, and pays them Danegeld, each ruling parts of England.source
• 871King Rhodri Mawr ("the Great") of Gwynedd annexes Seisyllwg, uniting most of Wales under his rule (approximate date).source
• 872Sancho III Mitarra (or Menditarra) becomes the founder and first 'king' of the independent Duchy of Gascony, with loose ties to the Frankish Kingdom.source
• 874Svatopluk I, ruler (knyaz) of Great Moravia, concludes a peace treaty at Forchheim (Northern Bavaria). He is able to expand his territories outside the Frankish sphere, and subjugates the Vistulans.source
• 875King Harald Fairhair of Norway subdues the rovers on the Orkney Islands and Shetland Islands, and adds them to his kingdom (approximate date).source
• 876At the invitation of Benevento, the newly-restored Byzantine fleet appears in the waters off Otranto. On the orders of Emperor Basil I, the Byzantines sail up the Adriatic Sea and reconquer part of southern Italy. The city of Bari is occupied in the name of the Byzantine Empire. Instead of holding it for his 'ally' Adelchis of Benevento, Basil makes it the capital of the new Byzantine Theme of Longobardia.source
• 876Viking leader Halfdan Ragnarsson formally establishes the Danish kingdom of York, after the removal of the puppet king Ricsige of Northumbria, and becomes the first monarch.source
• 876Emperor Seiwa abdicates the throne, in favor of his 7-year-old son Yōzei. Seiwa becomes a Buddhist priest; he appoints Fujiwara no Mototsune as regent (sesshō), who assists the child emperor.source
• 877December 8 – Louis the Stammerer is crowned by Hincmar as king (not emperor) of the West Frankish Kingdom, in the church of Compiègne. The imperial throne will remain vacant until 881.source
• 877Ceolwulf II is installed as puppet king of Mercia. The west of the kingdom comes under Ceolwulf's rule, while in the east the Five Boroughs begin as fortified Danish burhs.source
• 878Treaty of Wedmore: Guthrum agrees to a peace treaty and is baptised, taking the name of Aethelstan. England is divided between Wessex in the south, and the Vikings in the Danelaw up north. Guthrum returns to East Anglia.source
• 879King Charles the Fat becomes ruler of the Kingdom of Italy, after the abdication of his brother Carloman of Bavaria, who has been incapacitated by a stroke.source
• 880December – Treaty of Ribemont: Louis the Younger and the kings of the West Frankish Kingdom sign a treaty. The young Frankish monarch, Louis III, is reduced to merely Neustria.source
• 880Fujiwara no Mototsune, Japanese statesman, creates the position of regent (kampaku) for himself. The Fujiwara clan will be able to dominate the government for more than 3 centuries.source
• 883Svatopluk I, ruler (knyaz) of Great Moravia, conquers Lower Pannonia (today's Southwestern Hungary and Northern Croatia), during the succession strife in the East Frankish Kingdom (approximate date).source
• 884March 4 – Emperor Yōzei is forced to abdicate the throne by Fujiwara no Mototsune, chancellor (kampaku) of the Japanese royal court. He is succeeded by his great-uncle Kōkō.source
• 886King Alfred receives the formal submission of all of the citizens of England not under Viking rule, and adopts the title King of the Anglo-Saxons.source
• 888Adarnase IV managed to unify most Georgian lands (except for Kakheti and Abkhazia) and was crowned King of the Iberians, restoring the monarchy abolished three centuries prior.source
• 889April – The Japanese era Ninna ends and Kanpyō begins, lasting until 898.source
• 889In Italy, Forlì becomes a republic for the first time. The city is allied with the Ghibelline faction, in the medieval struggles between the Guelphs and Ghibellines.source
• 889Boris I, ruler (khan) of the Bulgarian Empire, abdicates the throne after a 37-year reign, and retires to a monastery. He is succeeded by his eldest son Vladimir, as monarch of Bulgaria. Vladimir falls under the influence of the old boyars; many remain anti-Christian and anti-Byzantine. He attempts to restore the former Frankish alliance, and to reestablish paganism.source
• 889In Portugal, the count of Coimbra, Hermenegildo Gutiérrez, reconquers Coimbra, which was temporarily lost after the first conquest of 878.source
• 890The sovereignty of Svatopluk I, ruler (knyaz) of Moravia, is confirmed in Bohemia. Lusatia becomes a part of his kingdom (approximate date).source
• 892Vladimir, ruler (knyaz) of the Bulgarian Empire, signs a military alliance with Arnulf of Carinthia of the East Frankish Kingdom. This alliance works against the pro-Byzantine policy of his father.source
• 893Galindo II Aznárez succeeds his father Aznar II Galíndez as count of Aragon (until 922).source
• 894Emperor Uda orders commercial relations (called Imperial Japanese embassies to China) to cease with China (approximate date).source
• 896November – Lambert II and Berengar I agree to sign a treaty at Pavia. Berengar receives the realm between the Adda and the Po, while the rest stays under the control of Lambert (including the March of Tuscany). They share Bergamo, and Lambert pledges to marry Gisela, Berengar's daughter.source
• 897Emperor Uda abdicates the throne after a ten year reign. He is succeeded by his 12-year-old son Daigo, as the 60th emperor of Japan.source