Frederick W. Ritter served in the Marine Corps as an engineer officer during World War II. He specifically served as a Vought F4U Corsair engineer. He trained at Parris Island, Jacksonville Naval Base, and attended Officer training at Quantico. He met his wife when he joined a church choir in Jacksonville, corresponding with her throughout the war. During the battle of Okinawa, he oversaw the maintenance of the Corvairs that protected the Navy from Kamikaze attacks. The collection includes Ritter's military documents, official paperwork, various letters, photographs, pins and badges, as well as magazines, articles, programs, and photographs from reunions and other postwar events related to his wartime experiences.