- Brown, Clarence J., 1927-1
- Broyhill, James T.1
- Burleson, Omar Truman, 1906-19911
- Byrd, Robert C.1
- Caddo Nation1
- Carey, Hugh L.1
- Carter, Jimmy, 1924-12
- Carter, Tim Lee, 1910-19871
- Cherokee Nation7
- Cheyenne and Arapaho Tribes3
- Chickasaw Nation28
- Chilocco Indian Agricultural School (Okla.)1
- Choctaw Nation of Oklahoma32
- Coalition of Northeastern Governors (U.S.)2
- Comanche Indian Tribe1
- Common Cause (U.S.)1
- Conyers, John, Jr., 1929-20191
- Cooley, Harold D. (Harold Dunbar), 1897-19741
- Corman, James C. (James Charles), 1920-20001
- Costle, Douglas1
