The real accounts of "Liver Eat'n Johnson", much better than than the Robert Redford Hollywood version....a must read.
Rumors, legends, and campfire tales abound about Johnson. Perhaps chief among them is this one: In 1847, his American Indian wife was killed by Crow Indians, which prompted Johnson to embark on a 20-year vendetta against the tribe, killing over 300 Crows. The legend says that he would cut out and eat the liver of each man killed, but it's quite possible that this only happened once and that he just pretended to eat the liver. In any case, he eventually became known as "Liver-Eating Johnson". Since eating the liver of a victim is a symbolic way of completing a revenge slaying, or assuming some qualities of the vanquished, credence might be given to this activity.
Another story is when Johnson was ambushed by a group of Blackfoot warriors in the dead of winter on a foray to visit his Flathead kin, a trip that would have been over five hundred miles. The Blackfoot planned to sell him to the Crow, his mortal enemies, for a handsome price. He was stripped to the waist, tied with leather thongs and put in a teepee with an inexperienced guard outside. Johnson managed to chew through the straps, then knocked out his young guard with a punch to the face, took his knife and scalped him, then quickly cut off one of his legs. He made his escape into the woods, and survived on the Blackfoot's leg until he reached the cabin of Del Que, his trapping partner, more dead than alive, a journey of about two hundred miles.