A diarchic Mongol-Tibetan administration in which the Sakya lama held nominal religious and political headship of Tibet under a 'priest-patron' relationship with the Yuan emperor, while the Yuan's Bureau of Buddhist and Tibetan Affairs (Xuanzheng Yuan) managed administrative and military rule through an appointed dpon-chen.
The Sakya-Yuan administrative structure collapsed by 1354 as the Phagmodrupa dynasty, led by Tai Situ Changchub Gyaltsen, overthrew Sakya authority and established control over central Tibet.
Standard academic survey of Tibetan history including the Mongol-Sakya period and the Yuan administrative relationship.