Within the Blackfoot nation, there were different societies to which people belonged, each of which had functions for the tribe.  There are stories which explain how these societies came to be instituted, and this one tells how the Society of Bulls began.

 

Then Iamo told them that, since they had all died and been restored to life again, they were no longer mortals but spirits, and he assigned to each of them a station in the invisible world. Only Mudjikewis’ place was, however, named. He was to direct the west wind. The brothers were commanded, as they had it in their power, to do good to the inhabitants of the earth, and to give all things with a liberal hand.