The Mongols, famously, were not much interested in religious conformity. People who managed to avoid being massacred during the Mongol invasions were at least unlikely, subsequently, to be persecuted for their religious beliefs. What interested the Mongols was that holy men of all religions should both pray for the Khan (for there was no knowing who might have the best hotline to heaven), and, at least as important, provide the regime with access to their specialist skills. The Mongols were nothing if not pragmatists.
— David Morgan (?) in the TLS
[you hear this a lot. I do wonder how psychologically true it ever was]