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 also drastically reduced in size and there was no practical need for a superior General rank, thus the proposal for General of the Armies was soon forgotten. In 1865, after the close of the American Civil War, Congress again revisited the idea of a superior General rank. The result was the creation of a special rank called "General of the Army of the United States", which was held by Ulysses S. Grant. This early version of General of the Army was in fact a four-star general officer rank although, unlike in modern times, Congress intended for only one Army officer