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.
@Pohl sure, but the reason European colonization of other places is focused on so much is due to scale and technology.
Scale and tech are what separates, say, the Shoah from Russian pogroms.
Scale and tech are also why so many people are still living with the aftermath. And that aftermath is why it's still relevant.