There have only been 4 men to attain this rank, it is the equivalent of O-11. The four men to attain this rank include, William D. Leahy, Ernest J. King, Chester W. Nimitz, and William F. Halsey.

The rank of Fleet Admiral was created on a temporary basis under Pub.L. 78-482 on December 14, 1944 and made permanent by Pub.L. 79-333 on March 23, 1946. This means one a Fleet Admiral, always a Fleet Admiral. Unless the commission was resigned the person holding the rank was always on active duty and would be paid in full.

This rank is actually not the highest military position in the Navy. The highest is actually the WOD for tomorrow! Since the end of World War II no officer has been promoted to Fleet Admiral since Halsey. The four fleet admirals were promoted to correspond with the promotions of the Generals in the Army.

The promotion dates for the Fleet Admirals are as follows, Dec 15, 17, 19 1944 and Dec 21 1945. The promotion dates for General of the Army are as follow Dec 16, 18, 20, and 21 1944. This was done on purpose to give a seniority order between both services. The Army eventually had 5 5-star Generals, Omar Bradley was promoted in 1950.