Hello /r/AskHistorians! I need help researching Native Americans in the Plains. Since I'm from the Rock Island area, I was curious to learn more about the Sauk Tribes and Chief BlackHawk. I'm working on a screenplay that has two half brothers (one 1/2 Native Am, one full) join together to fight a common enemy that controls much of the fur trade. I want to know where I should look for information on early White settlers in the 1800s Midwest, and the Natives during this time period. Although I may take some liberties historically, I would like the Native Americans be authentic and accurate.

So here's a background. Thank you all in advance, anything will help!

Screenplay Background:

    Setting: "Pioneer Times" in the Midwest.
    Protagonists: Same Native mother, different fathers.
    Premise: Brothers team-up to find a common enemy.

Writer Goals:


    Cinematic like a classic western
    Honest portrayal of the Natives
   Accurate portrayal of Fur Trade 
    Characters: well rounded, dynamic, and most importantly, authentic.