Home to 39 Native Tribes

Oklahoma has 39 federally recognized Native American tribes, more than any other state in the country, a legacy of the federal removal policy that forced dozens of tribes from their ancestral homelands east of the Mississippi to what was then designated Indian Territory beginning in the 1830s. The forced removal of the Five Civilized Tribes, including the Cherokee, Choctaw, Chickasaw, Creek, and Seminole, along routes that became known collectively as the Trail of Tears, killed an estimated 10,000 to 15,000 people. Oklahoma became a state in 1907, after the federal government opened Indian Territory to white settlement.

Source: Wikipedia