American Indians were generally at war with each other.

American Indians were generally at war with each other. Nor was slavery a foreign concept to them. They generally enslaved other tribes when they had the power to do so. [e.g. the Shawnee tribe would roast the captured men alive,  eat them and enslave the rest. The women generally were the commandants that would choose who would live and who would be digested.] So when a certain tribe of  Germanic tribes called Anglo-Saxon came, that was not particularly a new thing. Just more of the same except in one detail.  [See the  Ohio Frontier by Douglas Hurt published in 1996]

In Ohio the first Indians were destroyed by the Iroquois. So the Shawnee and other tribes chased them out until they in turn were chased out.