Events

• April 16 - Philip II of France enters Rouen, leading to the eventual unification of Normandy and France.
• April 8 - Congress of Bilino Polje: Ban Kulin officially declares his allegiance to the Roman Catholic Church and denounces heresy.
• June 23 - The Fleet of the Fourth Crusade enters the Bosphorus.
• July 17 - The armies of the Fourth Crusade capture Constantinople by assault; the Byzantine emperor Alexius III flees from his capital into exile.
• August 1 - The Fourth Crusade elevates Alexius IV as Byzantine Emperor, after the citizens of Constantinople proclaim as emperor Isaac II Angelus (Alexius IV's father).
• William de Braose, Fourth Lord of Bramber becomes the guardian of Arthur I, Duke of Brittany, and is possibly responsible for his death.
• Minamoto no Sanetomo becomes shogun of the Kamakura Shogunate
• Battle of Basiani: The Georgians defeat a Muslim coalition.
• The Almohads begin the conquest of the Balearic Islands.
• The Temple of Nataraja is completed by Chidanbaram of India.

Births

• Peter II of Savoy (d. 1268)

Deaths

• Peter of Blois, French poet and diplomat (b. 1135)
• Arthur I, Duke of Brittany (b. 1187)
• Dafydd ab Owain Gwynedd, King of Gwynedd

Heads of states

• France - Philippe II, Auguste King of France (reigned from 1180 to 1223)