By the American Revolution (1775–83), population growth in the thirteen original colonies had pushed most Native Americans inland across the Appalachian Mountains. Even there, the Native Americans had begun to see a few hardy white settlers, who had crossed the Appalachians to farm the fertile lands in the Ohio River valley. The Native Americans lived in small groups thinly spread across the countryside, and to the white frontiersmen, it seemed they were not making full use of the land. Therefore, the white settlers reasoned that the land was an open, unclaimed, untamed wilderness available for the taking.

The loss of their homelands along the coast and the continuing westward expansion of the United States led to strong resentment among the Native American peoples. When the American Revolution broke out in 1775, some thirty-five thousand Native American warriors lived in the frontier region west of the Appalachian...