Religion was exceptionally important to the Mongols as they had a central belief system through which everything they did was decided and justified. Genghis Khan himself used to travel to the top of a sacred mountain near his home before beginning a conquest or battle and pray. (Genghis Khan and the making of the modern world). They believed in the interaction of spirits with the temporal world, or Shamanism. At the head of this religion was the Shaman, he was responsible not only for the spiritual wellbeing of his tribe, but also its material wealth - and would be constantly trying to improve the tribe’s economic situation. The strength and political power that came with position was therefore great, and perhaps came close to rivalling even that of the Great Khan at times. One example of a situation like this was the conflict between Temujin and Kokochu; better known as Teb-Tengri ("Most Heavenly"). –See PDF on Shamanism-
For most of the remainder of Mongol rule, the Shaman remained as such, another servant of the Great Khan and Golden Family.
While they maintained a central belief system, the Mongols were also exceptionally liberal as to what other religions you could follow. As long as your loyalty and obligations to the Golden Family and Shaman were fulfilled, such as praying for the Great Khan to whichever religious deity you believed in, you were free to worship whichever religion you pleased - this led to several of the Great Khan's being Christian, others following Islam, and others the Hindu religion. The liberal attitude they displayed towards religion helped massively in assimilating new countries into the Mongol Empire, as there were no attempts to impose a religious system on the populace, one of the more disliked common practices during occupation. Some historians argue that this religious liberalism was actually the Mongols 'playing it safe' in terms of the afterlife, believing that by treating all religions well and not