I don't know about young Sam Clemens' experience with native Americans, but
I
do remember that Keokuk, Iowa was originally reserved as a territory for
multi-racial offspring with one native American parent (how in the world can
that statement be clearly made in this century without falling into the
"half-breed" language of the 19th century?) Since he moved to Keokuk while
still relatively young, I gather he had the opportunity to live among native
Americans.

Did he have any early experience of the Mormons across the river in Nauvoo
City, Illinois? Their presence certainly could have shaped his later writing
concerning the Mormons of Utah.

Dennis Kelly