1400S: Decade of the Gregorian calendar (1400‐1409)

It is distinct from the decade known as the 141th decade which began on January 1, 1401. and ended on December 31, 1410.

• Henry IV stops the Epiphany Rising. He kills the people who try to have Richard II of England restored as King.
• The princes of the German states remove Wenceslaus as Holy Roman Emperor.
• Rupert is elected as Holy Roman Emperor.
• Owain Glyndŵr is called Prince of Wales by his followers. He begins attacking Englishplaces in north-east Wales.
• Manuel II Palaiologos becomes the first (and last) Byzantine Emperor to visit England.
• The Medici family becomes powerful in Florence.

Births

• Luca della Robbia, Florentine sculptor
• Owen Tudor, Welsh courtier (d. 1461)

Deaths

• January 5 – John Montacute, 3rd Earl of Salisbury, English politician (executed)
• January 5 – Thomas Holland, 1st Duke of Surrey, English politician (executed)
• January 13 – Thomas le Despenser, 1st Earl of Gloucester, English politician (executed)
• January 16 – John Holland, 1st Duke of Exeter, English politician (executed)
• February 14 – King Richard II of England (probably murdered)
• April 28 – Baldus de Ubaldis, Italian jurist
• June 5 – Frederick, Duke of Brunswick-Lüneburg, rival Holy Roman Emperor
• October 25 – Geoffrey Chaucer, English poet
• December 24 – Archibald the Grim, Scottish magnate
• Narayana Pandit, Indian mathematician

• Timur raids the city of Baghdad in the Jalayirid Empire.
• A civil war starts in the Majapahit Empire in present-day Indonesia.

Births

• May 12 – Emperor Shoko of Japan
• October 27 – Catherine of Valois, queen of Henry VI of England
• December 21 – Tommaso Masaccio, Italian painter

Deaths

• October 20 – Klaus Störtebeker, German pirate
• Anabella Drummond, queen of Scotland

• King Jogaila of the Poland–Lithuania union marries Anna of Celje. She is a granddaughter of Casimir III of Poland.
• May 21 – Following the death of Queen Maria of Sicily, her husband Martin I of Sicily marries Blanche of Navarre.
• The University of Würzburg, Germany, is founded.
• The Great Comet of 1402 is sighted.

Births

• September 29 – Fernando, the Saint Prince of Portugal
• Leonor of Aragon, Queen of Portugal

Deaths

• March 26 – David Stewart, Duke of Rothesay, heir to the throne of Scotland
• May 3 – João Anes, Archbishop of Lisbon
• July 13 – Jianwen Emperor of China

• February 7 – King Henry IV of England marries Joanna of Navarre.
• Henry 'Hotspur' Percy forms an alliance with Welsh rebel Owain Glyndŵr.
• July 21 – Battle of Shrewsbury: King Henry IV of England defeats a rebel army led by "Hotspur" Percy. Percy is killed in the battle by an arrow in his face.
• In China, the Ming Emperor Yongle moves the capital from Nanjing to Beijing.
• The world's first quarantine station is built in Venice. It is to protect against the Black Death.
• Stefan Lazarević makes Belgrade the capital of the Serbian Despotate.

Births

• January 17 – George Kastrioti of Albania
• February 22 – King Charles VII of France
• June 11 – John IV, Duke of Brabant
• Robert Wingfield, English politician
• Louis III of Naples

Deaths

• May 10 – Katherine Swynford, widow of John of Gaunt
• May 12 – William de Lode, English prior
• July 23 – Thomas Percy, 1st Earl of Worcester, English rebel (executed)
• Beyazid, Ottoman Sultan
• Hajji Zayn al-Attar, Persian physician
• Đurađ II Stracimirović, Serbian nobleman

• June 14 – Rebel leader Owain Glyndŵr allies with the French against the English.
• October 17 – Pope Innocent VII succeeds Pope Boniface IX as the 204th pope.
• November 19 – St. Elizabeth's flood ruins parts of Flanders, Zeeland and Holland.
• Jean de Béthencourt becomes the first ruler of the Kingdom of the Canary Islands.
• Stephan Tvrtko II succeeds Stefan Ostoja as King of Bosnia.
• The University of Turin is founded.

Births

• February 9 – Constantine XI, last Byzantine Emperor
• February 18 – Leon Battista Alberti, Italian painter, poet, and philosopher
• March 25 – (baptism) – John Beaufort, 1st Duke of Somerset, English military leader
• June – Murad II, Ottoman Sultan
• July 25 – Philip I, Duke of Brabant
• September 10 – Gilles de Rais, French aristocrat
• October 14 – Marie of Anjou, queen of Charles VII of France
• Yamana Sōzen, Japanese warlord and monk

Deaths

• April 27 – Philip II, Duke of Burgundy
• September 14 – Duke Albert IV of Austria
• September 23 – Eleanor of Arborea, ruler of Sardinia
• September 27 – William of Wykeham, English bishop and statesman
• October 1 – Pope Boniface IX
• October 15 – Marie Valois, French princess
• December 13 – Albert, Count of Holland

• June 8 – Archbishop Richard le Scrope of York and Thomas Mowbray, Earl of Norfolk, were executed in York on Henry IV's orders.
• Bath Abbey is built in England.
• First written record of whiskey being drank is recorded in Ireland. It was distilled by Catholic monks.
• Early feminist Christine de Pizan writes The Book of the City of Ladies.

Births

• March 6 – King John II of Castile
• May 6 – George Kastrioti, Albanian national hero
• October 18 – Pope Pius II

Deaths

• February 14 – Timur, Turco-Mongol monarch and conqueror
• May 29 – Philippe de Mézières, advisor to Charles V of France

• April 4 – James I becomes King of Scotland.
• October 26 – Eric of Pomerania marries Philippa, daughter of Henry IV of England.
• November 30 – Pope Gregory XII succeeds Pope Innocent VII as the 205th pope.
• December 25 – John II becomes King of Castile.
• Construction of the Forbidden City begins in Beijing.

Births

• September 26 – Thomas de Ros, 9th Baron de Ros, English soldier and politician
• Ulrich II of Celje
• Lorenzo Valla, humanist

Deaths

• January 6 – Roger Walden, English bishop
• March 19 – Ibn Khaldun, Arab historian
• April 4 – King Robert III of Scotland
• May 4 – Coluccio Salutati, Chancellor of Florence
• July 15 – Duke William of Austria
• August 28 – John de Sutton V
• November 1 – Joanna, Duchess of Brabant
• November 6 – Pope Innocent VII
• December 25 – King Henry III of Castile

• April 10 – The fifth Karmapa finally visits the Ming Dynasty capital, then at Nanjing.
• November 23 – The Duke of Orleans is killed; war starts again between the Burgundians and his followers.
• Rudolfo Belenzani leads a revolt against Bishop Georg von Liechtenstein in Trento, Italy.

Births

• March 15 – Jacob, Margrave of Baden-Baden
• August 27 – Ashikaga Yoshikazu, Japanese shogun
• Thomas de Littleton, English judge

Deaths

• March 7 – Francesco I Gonzaga, ruler of Mantua
• April 23 – Olivier de Clisson, French soldier
• November 23 – Louis of Valois, Duke of Orléans, brother of Charles VI of France
• Pero López de Ayala, Spanish soldier
• Tokugawa Chikauji, Japanese nobleman

• December 13 – The Order of the Dragon is founded under King Sigismund of Hungary.
• Henry, Prince of Wales retakes Aberystwyth from Owain Glyndŵr.

Births

• April 8 – Jadwiga of Lithuania, Polish princess

Deaths

• May 31 – Ashikaga Yoshimitsu, Japanese shogun
• Pope Matthew of Alexandria
• Elizabeth le Despenser, English noblewoman
• John VII Palaiologos, Byzantine Emperor
• Miran Shah, son of Timur

• January 1 – The Welsh surrender Harlech Castle to the English.
• December 2 – The University of Leipzig opens.
• Martin I of Aragon becomes King of Sicily.
• Ulugh Beg becomes governor of Samarkand.
• Venice buys the port of Zadar from Hungary.

Births

• January 16 – René of Anjou
• October 1 – Karl Knutsson, King of Sweden
• Bernardo Rossellino, Florentine sculptor and architect

Deaths

• May 13 – Jan z Tarnowa, Polish nobleman
• May 22 – Blanche of England, sister of King Henry V
• July 25 – King Martin I of Sicily
• Thomas Merke, English bishop