Battle of Qatwan

September 9, 1141

The Qara Khitai khan Yelu Dashi, last of the Khitan nobility, destroyed a Seljuk army under Sultan Sanjar on the Qatwan steppe north of Samarkand. News traveled west and curdled into the Prester John legend. The Seljuk eastern frontier collapsed for good, and the Central Asian cities of Bukhara and Samarkand passed under the rule of Buddhist overlords for the first time in centuries.