1236

Events

Spring - A fleet consisting of ships from the republics of Venice, Genoa and Pisa arrive at Constantinople. It is headed by Geoffrey II of Villehardouin, ruler of Achaea, who brings 100 of his own knights, 300 cross-bowman, and 500 archers. Geoffrey, formally a vassal of Emperor John I of Constantinople, breaks the blockade of the city, sinks 15 Byzantine ships and enters the Golden Horn. A treaty is signed for two years after the intervention of Angelo Sanudo, duke of Archipelago.

June 20 - Treaty of Kremmen: Duke Wartislaw III recognizes the seignory of Henry Borwin III, lord of Rostock, after his successful expedition against Wartislaw, in which he has conquered Circipania, including the cities of Gnoien and Kalen. Meanwhile, Swietopelk II, Duke of Pomerania conquers Schlawe and Stolp, the eastern part of Pomerania. To ease the tensions with Brandenburg, Wartislaw signs the Kremmen agreement.
June - The 16-year-old Alexander Nevsky is elected by the Novgorodians as prince of Novgorod, beseeching the young Kievan noble to take charge of the city's military affairs.
June 29 - Siege of Córdoba: Castilian forces under King Ferdinand III capture Muslim Córdoba from Emir Ibn Hud, as part of the Reconquista of the Iberian Peninsula.
July - At a diet in Piacenza, Emperor Frederick II proclaims his wish to recover all Italy for the Holy Roman Empire.
September 22 - Battle of Saule: The Lithuanians and Semigallians defeat the Livonian Brothers of the Sword, at Šiauliai in Lithuania.

January 14 - King Henry III marries the 14-year-old Eleanor of Provence, one of the four daughters of Raimond Berenguer, count of Provence. The ceremony takes place at Canterbury Cathedral, while Simon de Montfort, as Lord High Steward, takes care of the banquet and kitchen arrangements. Eleanor is crowned queen at Westminster Abbey shortly afterward.
A tournament at Tickhill turns into a battle between northerners and southerners, but peace is restored by papal legate Otto of Tonengo.

The Mongols under Batu Khan, eldest of Jochi, sweep across Central Asia. They settle in the Russian steppe, curtailing the power of the Kievan Rus', extracting tribute from their neighbors, and disrupting their relationship with the Byzantine Empire.
Autumn - Siege of Bilär: The Mongols under Batu Khan capture the capital city of Bilär after a siege that lasts for 45 days. The Volga Bulgars are defeated within the year, as are the Kipchaks and Alans.
Mongol–Song War: The Mongols under Ögedei Khan penetrate deep into the Southern Song. The important city of Xiangyang, gateway to the Yangtze plain, capitulates to the Mongols.

October 10 - Razia Sultana, daughter of Mamluk Sultan Shamsuddin Iltutmish, becomes the first female Muslim ruler of the Indian subcontinent, deposing her half-brother, Ruknuddin Firuz, as sultan of the Delhi Sultanate.
King Kalinga Magha is expelled from Polonnaruwa to Jaffna, capital of the Jaffna Kingdom.

Kouroukan Fouga, the constitution of the Mali Empire, is created by an assembly of nobles of the Mandinka clan.

The Goryeo court in Korea orders the preparation of another set of woodblocks for printing the Buddhist Tripiṭaka – which is intended both to gain protection against the Mongol invaders and to replace the earlier 11th century set that has been destroyed by the Mongols.

Pope Gregory IX condemns the links that both the Knights Templer and Knights Hospitaller have with the Assassin fighters in the Middle East. He issues a bull preventing further contact with the Assassins.
May 6 - Roger of Wendover, English Benedictine monk and chronicler, dies at St Albans Abbey. His chronicle is continued by Matthew Paris.