Life
Ahmad Sanjar (effective ruler of the east from 1097, sultan 1118–1157) governed Khurasan and the Seljuk east through a long reign of both splendor and mounting crisis. He faced the rise of the Kara-Khitai, who defeated him at the Qatwan steppe (1141), and finally a revolt of Oghuz Turkmen who captured and held him prisoner. His death in 1157 effectively ended the Great Seljuk Empire, which dissolved into successor states.