The Tuscarora were allowed to join after being booted from their homeland, thus the Six Nations

That was the story as I knew it. The Tuscarora were a way south in what was in the process of becoming North Carolina (early eighteenth century). When they'd had enough of playing nice with settlers who stole their children and "squatted" their land, and they came off worse in fighting (glorified by the name of the Tuscarora War), they migrated north, invited by the Five Nations as their brothers of the Sixth. Events that took place between about 1710 and 1720.