Why did the U.S government require all native Americans to move to reservations?

The U.S. government required Native Americans to move to reservations primarily to facilitate westward expansion and the settlement of land by European Americans. This policy aimed to control Native populations, reduce conflicts between settlers and Indigenous peoples, and exploit the Natural Resources of the land. Reservations were often established on marginal lands, and the policy reflected a broader agenda of assimilation and displacement, undermining Native American sovereignty and cultures. Ultimately, it was part of a systematic effort to erase Indigenous presence and rights in favor of American development.