General-in-chief military forces in the field, as the generals-in-chief did in the 19th century. The rank of "General of the Armies of the United States" was conferred upon General John J. Pershing in 1919 and to Lieutenant General George Washington (posthumously) in 1975 by acts of Congress. Washington's date of rank was retroactively dated to 1799, so that he will always be the senior ranking general of the United States Army. (American general ranks and titles may be a little confusing; however, as reference is cited the public domain information of the Center for Military History of the United States Army
General of the Armies of the Armies is equivalent to the Admiral of the Navy and is senior to General of the Army, General of the Air Force, and Fleet Admiral. Appointment to the rank or grade of General of the Armies of the United States has a history spanning over two centuries. In the course of its existence the authority and seniority of the rank, and perceptions by both the American public and the military establishment, have varied. The first mention of the rank "General of the Armies" was in an Act of the United States Congress on March 3, 1799. Congress provided: