January 18 – King Henry I of Cyprus ("the Fat") dies and is succeeded by his son Hugh II, who is only a few months old. His mother, Queen Plaisance of Antioch, claims the regency of Cyprus and the titular regency of Jerusalem. The High Court of Cyprus confirms her position, but the barons of Outremer require her attendance in person before they will recognize her. John of Ibelin, count of Jaffa, remains as bailli, and Plaisance contemplates marrying John's youthful son Balian. Meanwhile, King Louis IX of France ("the Saint"), still staying at Acre, continues to administer the government.[1]
August 6 – King Henry III leads an expedition to Gascony, to repel a rumoured invasion from Castile.[3] Meanwhile, Simon de Montfort returns from Gascony where he allies himself with the barons who oppose Henry.
Henry III meets with the nobles and church leaders to reaffirm the validity of Magna Carta in exchange for taxation.[4]
May – Louis IX of France ("the Saint") dispatches William of Rubruck from Constantinople on a missionary journey to Karakorum to seek an alliance against Syrian and Egyptian Muslims.[5]
October – Pope Innocent IV returns to Rome, after being deposed for 9 years by former Emperor Frederick II, whose clash forms an important chapter in the conflict between the Papal States and the Holy Roman Empire.
Innocent IV offers the crown of Sicily, which he controls, to Richard of Cornwall and Charles of Anjou, both of whom refuse, and later to the 8-year-old Edmund, son of Henry III of England.