Mansur Khan's brother Sultan Said Khan (1514–1533) conquered the western Tarim Basin from the Dughlats in 1514 and set himself up in Kashgar forming the Yarkent Khanate. Thereafter the Moghulistan khanate was permanently divided, although Sultan Said Khan was nominally a vassal of Mansur Khan in Turpan. After Sultan Said Khan's death from high altitude edema in a failed 1533 attack on Tibet he was succeeded by Abdurashid Khan (1533–1565), who began his reign by executing a member of the Dughlat family. A nephew of the dead amir, Mirza Muhammad Haidar Dughlat fled to Mughal Empire in India and eventually conquered Kashmir, where he wrote a history of the Moghuls. Abdurrashid Khan also fought for control of (western) Moghulistan against the Kirghiz and the Kazakhs, but (western) Moghulistan was ultimately lost; thereafter the Moghuls were largely restricted to possession of the Tarim Basin.