Oklahoma is a state located in the South Central region of the United States of America. The state's name is derived from the Choctaw words okla and humma, meaning "red people", and is known informally by its nickname, The Sooner State. Formed from the Indian Territory on November 16, 1907, Oklahoma was the 46th state to enter the union. Its residents are known as Oklahomans, and its capital and largest city is Oklahoma City.