American policy toward Native Americans has been an evolving process. In the late nineteenth century, reformers, in efforts to "civilize" Indians, adapted the practice of educating native children in Indian Boarding Schools. These schools, which were primarily run by Christians, proved traumatic to Native American children, who were forbidden to speak their native languages, taught Christianity instead of their native religions and in numerous other ways forced to abandon their various Native American identities and adopt European-American culture. There are also many documented cases of sexual, physical and mental abuses occurring at these schools.
The Indian Citizenship Act of 1924 gave United States citizenship to Native Americans, in part because of an interest by many to see them merged with the American mainstream, and also because of the heroic service of many Native American veterans in World War 1.