1321 CE

King Edward II of England appoints the Archbishop of York; the Bishops of Carlisle, Worcester, and Winchester; the Earls of Pembroke, Hereford and Badlesmere; and six other people to negotiate with Scotland for a final peace treaty or an extension of the Pembroke treaty of 1319 before its expiration on Christmas Day. At Easter, the Byzantine civil war of 1321–1328 breaks out in the Byzantine Empire as Co-Emperor Andronikos III Palaiologos flees Constantinople to Adrianople, where he sets up his court and initiates an uprising against his grandfather, the Byzantine Emperor Andronikos II Palaiologos. The 24-year-old Andronikos is joined by Theodore Synadenos and John Kantakouzenos in the rebellion. Syrgiannes Palaiologos leads an expeditionary army towards the capital, forcing the emperor to negotiate. Forces of Edward II of England capture Leeds Castle in Kent after Margaret de Clare, wife of Bartholomew Badlesmere, refuses Queen Isabella admittance in her husband's absence. When the Queen seeks to force an entry, Lady Badlesmere instructs her archers to shoot at Isabella and her party, six of whom are killed. After Edward occupies the castle, Lady Badlesmere becomes the first woman ever to be imprisoned in the Tower of London. She will be freed on November 3, 1322.

In the 1320s, the 14th century.

Geopolitics & Diplomacy

January 19 – King Edward II of England appoints the Archbishop of York; the Bishops of Carlisle, Worcester, and Winchester; the Earls of Pembroke, Hereford and Badlesmere; and six other people to negotiate with Scotland for a final peace treaty or an extension of the Pembroke treaty of 1319 before its expiration on Christmas Day.source
January 20 – The English Parliament appoints a commission to inquire about illegal confederacies in Wales against the King.source
April 14 – Prince Wenceslaus of Płock allies with the Teutonic Knights of Poland and signs an agreement at the city of Golub, pledging to prevent Lithuanian troops from passing through his principality.source
June 6 – Andronikos II Palaiologos concludes a peace agreement and divides the Byzantine Empire in two. Andronikos III is recognized as co-emperor and receives Thrace and Macedonia. He rewards his followers and gives them towns and regions to administer. Adrianople becomes the new capital.source
July 15 – In England, the "Parliament of Whitebands" convenes with only 38 barons present, to remove suspect counsellors to the King.source
August 14 – King Edward II of England agrees to the demands from his barons to send Hugh Despenser the Elder and his son Hugh Despenser the Younger into exile. The Despensers helped Edward in the administration of his financial and land management affairs. This gives them both the opportunity to frustrate the ambitions of the barons and also the chance to enrich themselves.source
December 28 (Genko 1, 9th day of 12th month) – In Japan, Emperor Go-Daigo begins direct government as the cloistered rule of former Emperor Go-Uda ceases.source
The Anatolian Beylik of Teke, a frontier principality, is established by the Oghuz Turks after the decline of the Seljuk Sultanate of Rum.source

Conflict & Security

March 22 – The first Genkō era begins in Japan after the end of the Gen'ō era.source
March/April – peace talks at Bamburgh Castle end without agreementScotland source
April 19 – At Easter, the Byzantine civil war of 1321–1328 breaks out in the Byzantine Empire as Co-Emperor Andronikos III Palaiologos flees Constantinople to Adrianople, where he sets up his court and initiates an uprising against his grandfather, the Byzantine Emperor Andronikos II Palaiologos. The 24-year-old Andronikos is joined by Theodore Synadenos and John Kantakouzenos in the rebellion. Syrgiannes Palaiologos leads an expeditionary army towards the capital, forcing the emperor to negotiate.source
May 5 – Wars of the Rügen Succession: Dukes Otto I of Pomerania, Vartislav IV of Pomerania-Wolgast and Barnim III of Pomerania-Stettin reach a mutual inheritance contract with Vitslav III of Rügen.source
October 31 – Forces of Edward II of England capture Leeds Castle in Kent after Margaret de Clare, wife of Bartholomew Badlesmere, refuses Queen Isabella admittance in her husband's absence. When the Queen seeks to force an entry, Lady Badlesmere instructs her archers to shoot at Isabella and her party, six of whom are killed. After Edward occupies the castle, Lady Badlesmere becomes the first woman ever to be imprisoned in the Tower of London. She will be freed on November 3, 1322.source
November 27 – In northern Italy, Rinaldo dei Bonacolsi, Duke of Mantua, begins the siege of Mirandola against Francesco I Pico, Duke of Mirandola. Bonaclsi has Pico and his sons Francesco and Tommasino arrested and imprisoned in the Castel d'Ario. A siege of the castle begins the next day and lasts 33 days.source
December 8 – Confronting the rebellion of Thomas of Lancaster (his cousin), the Baron Badlesmere and Roger Mortimer, King Edward II of England arrives in Cirencester, then leads troops up the Severn Valley from Gloucester against the rebels.source
December 26 – Faced with an invasion of London during the rebellion of Thomas of Lancaster, by troops led by the English rebel, the Baron Badlesmere, King Edward II of England offers safe conduct for any rebels who come over to the royalist side, but orders the Sheriff of Gloucester to arrest Badlesmere.source
December 31 – The Duke of Mantua completes the siege of Mirandola, taking control of the Duchy, and then orders the castle of Duke Francesco I Pico to be destroyed.source
Winter – Byzantine civil war of 1321–1328: Syrgiannes Palaiologos switches support to Andronikos II Palaiologos, fleeing to Constantinople. Rewarded with the title of megas doux, he convinces the emperor to resume the war against Andronikos III.source

Religion & Belief

February 10 – By papal verdict announced in the Polish town of Brześć, the Teutonic Knights are ordered to return the coastal region of Gdańsk Pomerania to Poland, having annexed and occupied it since 1308. The Teutonic Order appeals the judgment and continues fighting against Poland, with a new Polish–Teutonic War breaking out soon afterward.source
April 12 – Sweden's governing council votes to bar foreigners from the royal palace, and to request that the Norwegian council admonish the regent Ingeborg to avoid taking advice from foreigners when making decisions. Ingeborg, who is serving as regent for her minor son, King Magnus, ruler of Sweden and Norway, has become infamous for making decisions without consultation from the councils of either of the kingdoms.source
May 8 – In Egypt's Mamluk Sultanate, a campaign by Muslims starts against the Christian settlements of the Coptic Orthodox Church. Over 60 churches and monasteries are burned.source
June 9 – Guillaume Agasse, the head of a leper house in Pamiers, claims in a statement to Bishop Jacques Founier (later Pope Benedict XII) that he had learned that more than fifty officials of leper houses had conspired with the Emirate of Granada to spread leprosy throughout France.source
June 23 – Pope John XXII approves a second inquiry into the matter of the canonization of Thomas Aquinas, with four commissioners to take testimony of witnesses.source
November 10 – Canonization of Thomas Aquinas: In Italy, a second inquiry begins at Fossanova, as three commissioners (Pandulpho de Sabbello; Petrus Ferri, Bishop of Anagni; and Andreas, Bishop of Terracina) take testimony from over 100 witnesses until November 27.source
The Spitakavor Monastery, near the Armenian town Yeghegnadzor, is completed.source
The Gračanica Monastery is founded by King Stefan Milutin, nicknamed "The Saint King", on the ruins of a 6th-century basilica, located in Kosovo.source
Roger Utlagh, Prior of the Order of St. John of Jerusalem, Kilmainham appointed Lord Chancellor of IrelandIreland source

Health & Medicine

January 30 – The Welsh Earls of Hereford, Arundel and Surrey, and 26 other people are forbidden from attending any meetings to discuss matters affecting King Edward II.source
May 16 – Johan de Bosco, a French person diagnosed with leprosy, claims that a fellow leper, "Geraldus" is attempting to spread their disease by contaminating wells, fountains, and rivers with bags of powder that will give leprosy to anyone who drinks from the water source. Rumors spread in southern France that French Jews are responsible, and is known as the 1321 lepers' plot.source
June 21 – King Philip V of France orders that all lepers be imprisoned and interrogated. Those found guilty, often under torture, are to be burnt at the stake.source

Culture & Society

May 4 – The German play Ludus de decem virginibus, a dramatization of the New Testament Parable of the Ten Virgins, is first performed.source
July 24 – A marriage contract is signed on behalf of Princess Euphemia, the 4-year-old sister of King Magnus of Sweden and Norway, and daughter of the regent Ingeborg of Norway, to eventually marry Albert of Mecklenburg the 3-year-old son of Henry I, Lord of Mecklenburg. The marriage will not take place until almost 15 years later.source
The University of Florence is established by the Republic of Florence.source
Approximate date – The Kebra Nagast ("The Glory of the Kings") is translated from Arabic to Ge'ez, according to its colophon.source

Births

January 6 – William de Greystoke, English landowner (died 1359)source
February 5 – John II, Marquess of Montferrat, Italian nobleman (died 1372)source
July 5 – Joan of the Tower, queen consort of Scotland (died 1362)source
August 7 – Bande Nawaz, Indian Sufi scholar and writer (died 1422)source
August 29 – John of Artois, Count of Eu, French nobleman (died 1387)source
John III of Trebizond ("Megas Komnenos"), Emperor of Trebizond (died 1362)source
James I, Aragonese nobleman (House of Barcelona) (died 1347)source
Nicholas, Count of Holstein-Rendsburg, German nobleman and co-ruler (died 1397)source
Al-Mansur Abu Bakr, Mamluk ruler of Egypt and Syria (died 1341)source
Zhang Shicheng, Chinese rebel leader and ruler (died 1367)source
He Zhen, Chinese nobleman, general, and politician (died 1388)source
Johann Wittenborg, German merchant and politician (died 1363)source
Louis I of Brzeg ("Louis the Wise"), Polish nobleman from the (House of Piast) (died 1398)source

Deaths

March 18 – Matthew III Csák, Hungarian nobleman and knightsource
April 8 – In the Delhi Sultanate of India, European Dominican missionaries who have accompanied Jordan Catala are killed while stranded on Salsette Island. Jordan escapes and continues his ministry.source
April 9 – Thomas of Tolentino, Italian preacher and missionary — The "Four Martyrs of Thane"source
April 17 – Blanche of Portugal, Portuguese princess (born 1259)source
April 27 – Nicolò Albertini, Italian friar, cardinal and statesmansource
May 31 – Birger Magnusson, king of Sweden (House of Bjälbo)source
July 1 – María de Molina, queen of Castile and León (born 1265)source
July 1 – María de Molina, grandmother of and regent for 12-year-old King Alfonso XI of Castile, dies at the age of 56, two relatives assume the regency and split Castile between themselves while chaos exists inside the Spanish kingdom. Alfonso's uncle, Don Juan Manuel de Ivrea, and cousin Juan de Castilla y Haro (called Juan el Tuerto or Juan the One-Eyed) remain in power until Alfonso XI reaches majority on 13 August 1325.source
July 31 – Ibn al-Banna' al-Marrakushi, Almohad mathematiciansource
September 14 – Italian author Dante Alighieri, known for The Inferno, dies of malaria at Ravenna after having undertaken a diplomatic mission in the Republic of Venice.source
September 14 – Dante Alighieri, Italian poet and writer (born 1265)source
October 29 – Stefan Milutin, Serbian king (born 1253)source
October 29 – King Stefan Milutin of Serbia dies after a 39-year reign. His son Stefan Konstantin claims the throne, but Konstantin's elder half-brother Stefan Dečanski starts a civil war and succeeds him.source
November 9 – Walter Langton, English cleric and bishop (born 1243)source