Honestly after all the Native Americans went through, give them the whole state at least. People in the United States speak and reflect often about the atrocities of slavery. We need to equally reflect on and remember the atrocities against Native Americans.
What do you mean "them"? You do realize that there were many different tribes who had very drastically different interactions with the US, right?
http://www.emersonkent.com/map_archive/native_american_tribe...
Maybe counties would be a better unit to consider.