The history of federal policy toward Native Americans has reflected changing ideas about whether Indians should be assimilated into white society or whether tribes should retain their sovereignty—their right to be independent and self-governing entities. Native Americans have always maintained that each individual tribe is a sovereign nation and should therefore be authorized to govern itself without outside influence. Official recognition of Native American sovereignty has fluctuated according to the beliefs of presidents, Congress, and the U.S. Supreme Court. Consequently, the rights of Native Americans have been expanded and curtailed at various times throughout the nation's history.

When Europeans first colonized North America, each settlement recognized its neighboring Indian tribes as self-governing, independent entities. The settlers negotiated treaties with Indians to secure peace and regulate trade and the expansion of white settlements. After the Revolutionary War, the U.S. Constitution gave Congress "plenary" power over all...