1233

Events

War of the Lombards: Lombard forces at Kyrenia surrender to John of Beirut, after a 10-month siege. The defenders, with their personal belongings, are allowed to retire to Tyre. Captured prisoners are exchanged for those held by Richard Filangieri, commander of the Lombards, at Tyre. Cyprus is wholly restored under the rule of the 16-year-old King Henry I. His vassals are rewarded, and loans that they have made are repaid.
August 20 - Oath of Bereg: King Andrew II of Hungary vows to the Holy See that he will not employ Jews and Muslims to administer royal revenues, which causes diplomatic complaints and ecclesiastical censures.
Winter - Reconquista: King Ferdinand III of Castile conquers the cities of Trujillo and Úbeda. The Castilian army besieges the city of Peniscola. Ferdinand forces Ibn Hud, ruler of the Taifa of Zaragoza, to sign a truce.

August - Richard Marshal, 3rd Earl of Pembroke, signs an alliance with Llywelyn the Great, to join forces to revolt against King Henry III. Richard is faced by demands from royal bailiffs in September – where the garrison of Usk Castle is forced to surrender.
November - Henry III's army camped at Grosmont Castle is attacked in the night, by a force of Welsh and English rebels. Several of Henry's supporters are captured, and the castle is returned to Hubert de Burgh, one of the rebels.

May 29 - Mongol–Jin War: The Mongol army led by Ögedei Khan captures Kaifeng, capital of the Jin dynasty, after the 13-month Siege of [Kaifeng (1232)]. The Mongols plunder the city, while Emperor Aizong of Jin flees for the town of Caizhou. Meanwhile, Ögedei departs and leaves the final conquest to his favoured general, Subutai.
December - Siege of Caizhou: The Mongols under Ögedei Khan besiege Caizhou and ally themselves with the Chinese Song dynasty to eliminate the Jin Dynasty.

Pope Gregory IX establishes the Papal Inquisition, to regularize the persecution of heresy.