The 31st Infantry Division was a unit of the Army National Guard in World War I and World War II. It was originally activated as the 10th, a division established in early 1917 consisting of Alabama, Florida, and Georgia national guardsmen. By the end of that same year, the 10th Division became the 31st.
- Mobilized: 25 November 1940 (National Guard Division from Alabama, Florida, Louisiana, and Mississippi).
- Overseas: 12 March 1944.
- Campaigns: New Guinea, Southern Philippines.
- Distinguished Unit Citations: 1.
- Awards: MH-1; DSC-7; DSM-3; SS-178; LM-11; DFC-1; SM-73; BS-948; AM-77.
- Commanders: Maj. Gen. John C. Persons (25 November 1940 – September 1944), Maj. Gen. Clarence A. Martin (September 1944 to inactivation).
- Returned to U.S.: 12 December 1945.
- Inactivated: 21 December 1945.