That seems to be the way the world operates and it's done so for many centuries. One culture displaces another and is displaced in its turn. One economic system gives way to another and so it goes.
It isn't just other races that get the shaft. Take a look at the Highland Clearances or the Famine in Ireland.
Actually, the Indians made good customers, trading valuable furs for what the Europeans considered trinkets but the land became more valuable than the fur so off we go to Oklahoma!
I can't think of any places where the aboriginal inhabitants are living on their ancestral land and have full control of it.

troll