Ögedei Khan

Ögedei Khan (c. 1186 – 11 December 1241) was the third son of Genghis Khan and the second Great Khan of the Mongol Empire, succeeding his father on 13 September 1229 and ruling until his death.

He was killed by the Assassins on 11 December 1241, ending his 12-year rule over the Mongol Empire.

Reference

 * Assassin's Creed: Memories