The displacement of Native American peoples from the region between the Appalachian Mountains and the Mississippi River resulted from a convergence of devastating factors:
European diseases—smallpox, measles, influenza—decimated populations with no immunity, destroying communities' capacity to resist.
Superior European firearms and tactics led to military defeats, loss of hunting grounds, and territorial concessions.
The fur trade created reliance on European goods (guns, metal tools), making tribes vulnerable to exploitation and reducing self-sufficiency.
Christianity, European social structures, and new customs undermined traditional beliefs and social cohesion.
Growing European populations demanded farmland, leading to treaties, forced removal, and coercive land cessions.
Colonial and U.S. policies favored white settlement through reservations, allotment systems, and legal frameworks that eroded communal land tenure.
Experiences varied among nations; some resisted effectively or negotiated better terms, but the overall trajectory favored European-American expansion.