Douglas Hancock Cooper Johnston (October 16, 1856 – June 28, 1939, Chickasaw), also known as "Douglas Henry Johnston", was a tribal leader who served as the last elected governor of the Chickasaw Nation from 1898 to 1902. He was re-elected in 1904 and, after the Dawes Act changed how tribal lands were allocated and regulated in Indian Territory to allow statehood in 1907, he was appointed by President Theodore Roosevelt in 1906 as governor of the tribe under federal authority. He served until his death in office in 1939.