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.
I think this map tries to apply European notions of borders and nation states where they don’t really apply.
It’s also wildly inaccurate as it’s a fictional map of an uncolonized America in 2015