- May 14 Battle of Lewes, 2nd Barons' War: Simon de Montfort the younger, Earl of Leicester, defeats English King Henry III
- Jun 18 The Parliament of Ireland meets at Castledermot in County Kildare, the first definitively known meeting of this Irish legislature.
- Aug 5 Anti-Jewish riots break out in Arnstadt Germany
- Sep 8 The Statute of Kalisz, guaranteeing Jews safety and personal liberties and giving battei din jurisdiction over Jewish matters, is promulgated by Boleslaus the Pious, Duke of Greater Poland.
- Oct 3 Comet said to predict death of Pope Urban IV is last seen
- Kublai Khan
Mongolian Emperor and Founder of the Yuan Dynasty
- May 26 Prince Koreyasu, Japanese shogun (d. 1326)
- Oct 2 Urbanus IV, [Jacques Pantaleon], French Pope (1261-64), dies