This chapter considers the changes wrought by the Mongol invasions. It first examines briefly the development of Muslim politics and literature in the pre-Mongol period, demonstrating how until the middle of the thirteenth century textual productionfocused largely on the Seljuq court. It then looks at the impact of Mongol rule, concentrating in particular on the political and religious consequences - the crisis of legitimacy caused by the Seljuq collapse and, the position of the Mongols before and after their conversion, and the persecution of Christians that intensified under Mongol rule.As a result, political discourse was infused with a new concern with unbelief, absent in the Seljuq period.