Admiral King was born in Lorain, Ohio on November 23, 1878. In 1897 he was admitted to the Naval Academy where he graduated with honors in 1901. During this time he also served on temporary duty aboard a cruiser during the Spanish American War of 1898.

King was promoted to Lieutenant Commander in 1913 and given the command of the destroyer Terry in 1914. During the period between the two World Wars, King served in many capacities including Commander, Submarine Base, New London and Commanding Officer for both the S-4 and S-51 Rescue and Salvage Forces, for both of which, he received Navy citations.

Admiral King has been described as having a violent temper and an abrasive personality, however, he was respected professionally by both American and Allied leaders.

Franklin D. Roosevelt appointed Admiral King as Commander in Chief of the U.S. Fleet in December of 1941 and as Chief of Naval Operations in 1942. In 1944 Admiral King was appoint to the newly created rank of Fleet Admiral. He retired from the Navy in 1945.

In 1947 he suffered the first of a series of strokes and on July 25, 1956, Fleet Admiral Ernest J. King passed away in Portsmouth, New Hampshire and was buried at Annapolis, Maryland.