At the time of Genghis Khan, the religion of medieval Mongolia was a kind of animistic shamanism. The principal deity was Tenggiri, the blue sky. While other gods existed, the religion lacked the sense of a pantheon of personalities in the Greek model. Instead, gods were mysterious and obscure. Those who had some knowledge of the divine played the role of shamans. Their primary activities involved practicing various forms of magic, including weather magic and divination. The shamans were defined by their deep insight of the world. This knowledge could be gained by channeling spirits that allowed them to travel through the dimensions of the world and conduct spiritual healing where the world was not in balance.
Great emphasis was placed around co-existing with the spirits of the world around them. This peace between humans and spirits was maintained through a series of taboos, or forbidden behavior. For instance, it was forbidden to urinate in a river, for fear of offending the river spirit. One could not pass a knife through fire, lest the fire spirit think this was an attempt to cut it. Anything struck by lightning had to be purified if they were to be touched afterwards. The power of the spirit world could be harnessed as well for human advantage. For instance, before battle it was customary to raise a Tuq, or ceremonial banner. An ancestral spirit could be summoned to aid its holders. But only after being enticed with a human sacrifice.
– A few thoughts from your friend Saxo