固始汗
The Oirats converted to Tibetan Buddhism around 1615, and it was not long before they became involved in the conflict between the Gelug and Karma Kagyu schools. At the request of the Gelug school, in 1637, Güshi Khan, the leader of the Khoshuts in Koko Nor, defeated Choghtu Khong Tayiji (1581-1637), the Khalkha prince who supported the Karma Kagyu school.