Plains medicine men were believed to be in close contact with the
spiritual world, and dictated the ceremonial life of the tribes.  Regarded
as a holy man, the shaman advised on future events and guided people in
rituals.  In order for the spirit world to "select" a medicine man, a boy
of eleven or twelve would go alone into the wilderness for several days to
seek the spirit protector.  Spirits would appear to him in a vision,
taking either an animal or human form.  If the boy's visions were deemed
significant, he would be introduced to the religious societies and
instructed in the chants and rituals.  The engraving above shows Medicine
Elk, a Sioux.