Miller enlisted in the U.S. Navy, joining the racially segregated Messman Branch as a Mess Attendant, Third Class.
On September 16, 1939, Doris Miller enlisted in the United States Navy in Dallas, Texas, seeking opportunity and escape from the limited prospects of Depression-era rural Texas. Like nearly all African American sailors of the time, he was assigned to the Messman Branch, the only occupational specialty officially open to Black enlisted men under the Navy's segregation policies.
As a Mess Attendant, Miller's duties included cooking, serving meals to officers, shining shoes, and other menial and domestic labor aboard ship, regardless of his physical abilities or intelligence. After training at Naval Station Norfolk, he was assigned to the ammunition ship USS Pyro, and in January 1940 he was transferred to the battleship USS West Virginia, where he would also become the ship's heavyweight boxing champion.
Miller's enlistment illustrates the systemic racial barriers Black Americans faced even while volunteering to serve their country: talented, capable men were funneled into subservient roles solely because of race, with promotion opportunities and combat training denied to them. His placement aboard the West Virginia would prove historic, as it was there, on December 7, 1941, that Miller would defy the limitations placed upon him and perform actions during the Pearl Harbor attack that made him one of the most celebrated heroes of World War II and a lasting symbol in the fight to desegregate the U.S. armed forces.