1204

Events 
 February – Byzantine emperor Alexius IV is overthrown in a revolution, and Alexius V is proclaimed emperor.
 April 12 – The Fourth Crusade take Constantinople by storm, and pillage the city for three days. End of the Fourth Crusade.
 May 16 – Baldwin, Count of Flanders is crowned emperor of the Latin Empire a week after his election by the members of the Fourth Crusade.
 Theodore I Lascaris flees to Nicaea after the capture of Constantinople, and establishes the Empire of Nicaea; Byzantine successor states are also established in Epirus and Trebizond.
 Boniface of Montferrat, a leader of the Fourth Crusade, founds the Kingdom of Thessalonica.
 The writings of French theologian Amalric of Bena are condemned by the University of Paris and Pope Innocent III.
 Valdemar II, King of Denmark, is recognized as king in Norway.
 Angers and Normandy are recaptured from England by Philip II of France.
 The Cistercian convent of Port-Royal is established.
 The district of Cham becomes subject to Bavaria.
 Philip of Swabia becomes a subject of Hermann I of Thuringia.
 Beaulieu Abbey founded.
 Jersey enjoys self-government thanks to the division of the Duchy of Normandy.
 Births 
 Haakon IV, King of Norway (died 1263)
 Heinrich Raspe, Landgraf of Thuringia (died 1247)
 Abû 'Uthmân Sa'îd Hakam al Qurashi, Ra'îs of Manûrqa (died 1282)

 Deaths 
 January 1 – King Haakon III of Norway
 February 8 – Alexius IV Angelus, Byzantine Emperor
 March 31 – Eleanor of Aquitaine, queen of France and England
 August 11 – King Guttorm of Norway
 August 14 – Minamoto no Yoriie, Japanese shogun (born 1182)
 October 21 – Robert de Beaumont, 4th Earl of Leicester
 December 13 – Maimonides, Spanish rabbi and philosopher (born 1135)
 Ban Kulin – ruler of Bosnia (born 1163)
 Amalric of Bena, French theologian
 William de Burgh, English politician
 Emeric of Hungary (born 1174)
 Isaac II Angelus, Byzantine Emperor
 Suleiman II of Rum
 David Soslani, Prince of Ossetia