Some of those mountain men were tough, eg Hugh Glass. There is an excellent 1971 movie loosely based on his life, ‘Man in the Wilderness’…terribly wounded in an attack by a grizzly, he nonetheless survived and made his way back 200 miles to ‘civilisation’: http://en.wikipedia.org/wiki/Hugh_Glass
Now remade as The Revenant – but nowhere near as good.
Also ‘Jeremiah Johnson’ another of my favourite movies; The Mountain Men 1980, Death Hunt 1981, Daniel Boone 1936…
The ‘Mad Trapper of Rat River’ aka Albert Johnson still presents an interesting mystery: http://en.wikipedia.org/wiki/Albert_Johnson_%28criminal%29
MORE on the ‘Mad Trapper’: http://www.youtube.com/watch?v=c96YQ9yWbX0