On June 18, 1942, Bernard W Robinson, became the first African American ensign in the United States Navy. This is from an older article, but it is very informative.
"June 18, 1942: The First Black Naval Officer is Commissioned
Today marks the 70th anniversary of Bernard W. Robinson becoming the first African American Naval officer, commissioned in the US Naval Reserve. Robinson attended Harvard Medical School and became a prominent radiologist after the war. Dedicated to the care of veterans, Robinson served in the Veterans Administration Hospitals system for the remainder of his career, interrupted only by his re-enlistment in the Navy from 1953-55. Robinson passed away suddenly in his Allen Park, Michigan home on August 23rd, 1972.
Robinson’s commission marks one of many firsts for African Americans during WWII, despite unfavorable odds. African Americans were not only fighting for victory abroad, but also victory at home against racial prejudice. On the Home Front and the battlefronts, blacks encountered restrictions solely based on the color of their skin. The military was segregated and African Americans struggled to find jobs in defense factories. If they did manage to secure work, it was usually at a much lower pay than their white counterparts.
Robinson’s experiences mirror other successes, acts of courage, and achievements of African Americans throughout the war. The Tuskegee Airmen became the first black pilots of the war, with a stellar flying record. The Montford Point Marines, who served in the Marshall Islands, Saipan, Guam, Iwo Jima and Okinawa, became the first African American Marines in the Corps’ 167 year history. The all-black 761st Tank Battalion spent 183 days in continuous combat, far surpassing the average of 17 days in continuous service.
Recognizing the accomplishments and sacrifices of returning black veterans, Harry Truman desegregated the military in 1948. Proving their skill and leadership on the battlefield, former servicemen like Ralph Abernathy, Whitney Young and Medger Evers began to fight for the second part of the Double Victory campaign – Victory at Home- as they returned to the United States at the war’s conclusion."