Over time, the United States forced a series of treaties and land cessions by the tribes and established reservations for them in many western states. The ways Native Americans refer to themselves vary by region and generation, with many older Native Americans self-identifying as "Indians" or "American Indians", while younger Native Americans often identify as "Indigenous" or "Aboriginal".The term "Native American" has not traditionally included Native Hawaiians or certain Alaskan Natives, such as Aleut, Yup'ik, or Inuit peoples.
A vast variety of peoples, societies and cultures subsequently developed.
Expansion of European-American populations to the west after the American Revolution resulted in increasing pressure on Native American lands, warfare between the groups, and rising tensions. This resulted in the ethnic cleansing of many tribes, with the brutal, forced marches coming to be known as The Trail of Tears.