late edit: DISCLAIMER: The pictured map is not actually a representation of the territories before colonisation. It's a hypothetical map of what countries there might have been had the continent not been colonised, thus all the names and borders are fictional and have never existed.
For good actual maps, check out native-land.ca.
It's conceivable that someone could have been accepted into a tribe and grew up believing themselves to be Native American, but the whole confirmed-descent-from-primary-villain thing really blows that hypothesis out of the water.