1204

Events

* February - Byzantine emperor Alexius IV is overthrown in a revolution, and Alexius V is proclaimed emperor.
* April 13 - Fourth Crusade: The Crusaders take Constantinople by storm, and pillage the city for 3 days.
* 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.
* The Republic of Croatia becomes Hungary and Venice intermittantly.
* 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 captured 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 is founded.
* Guernsey and Jersey decide, after a plebiscite of wealthy land owners, to remain with the English crown after Normandy was recaptured by Philip II of France.
* Pope Innocent III proclaims the Albigensian Crusade against the Cathars of Languedoc.

Births

* Haakon IV, King of Norway (d. 1263)
* Heinrich Raspe, Landgraf of Thuringia (d. 1247)
* Abû 'Uthmân Sa'îd Hakam al Qurashi, Ra'îs of Manûrqa (d. 1282)

Deaths

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