Some of it was for lack of better words, invasion and forcing out of what used to be their land, some of it was retribution for natives siding with the British during the revolution and in the war after.
It doesn't justify the atrocities but American history classes usually skip between the beginning and end of the natives story, not the very murky and dark middle.
I'd not be quick to say that and I don't mean that in a 'both sides' kind of way.
Just look at the war that happened in Florida for 6 years
Some of it was for lack of better words, invasion and forcing out of what used to be their land, some of it was retribution for natives siding with the British during the revolution and in the war after.
It doesn't justify the atrocities but American history classes usually skip between the beginning and end of the natives story, not the very murky and dark middle.