The Arapaho people originated in the Upper Midwest, but conflict stemming from the Midwestern fur trade pushed them farther west until they settled on the plains and foothills of present-day Wyoming and Colorado around 1790. The Cheyenne, meanwhile, went on a similar migration, moving from their homelands near the Black Hills to the plains and mountains of Wyoming and Colorado by the early 1800s. Both nations were in conflict with the Lakota, who had aggressively expanded across the northern plains during the seventeenth and eighteenth centuries.