I put a lot of research into Big City to make it as respectful as possible. Big City was loosely based off of the Klamath Tribes, though some things had to be adapted to better fit the gameplay.
http://www.craterlakeinstitute.com/o...c/complete.htm
The story of the Big City volcano was also loosely based off of the mythology of the Klamath tribe:
http://en.wikipedia.org/wiki/Llao
However, the pelts had little to do with trading and more to do with wanting to incooperate shape-shifting, or Skin-walkers:
http://en.wikipedia.org/wiki/Skin-walker
Though it's worth mentioning Big City had to be completed in just a month, and I didn't have time to do college-level research. I tried my best to be respectful of the culture and history of Native American's, contrary to what was expected for the content(stereotypical Western's Indian's and such).