Army of the United States

The Army of the United States or Armies of the United States is the legal name of the "land forces of the United States" (United States Constitution, Article 2, Section 2, Clause 1 and United States Code, Title 10, Subtitle B, Chapter 301, Section 3001) and has been used in this context since at least 1841, as in the title: General Regulations for the Army of the United States. The Army, or Armies of the United States includes: the Regular Army, Army National Guard, and the Army Reserve, (as well as any volunteer or conscripted forces).

The Army of the United States (AUS) was also used as the official name for the conscription (U.S. term: draft) force of the United States Army that may be raised at the discretion of the United States Congress when the United States enters into a major armed conflict. The "Army of the United States," in this context, was used in World War II, the Korean War, and the Vietnam War.

The "Army of the United States" (AUS) was established in February 1941, in response to the increasing threat of the United States entering World War II. The Army of the United States saw a major expansion following the December 1941 attack on Pearl Harbor. It was considered the successor to the National Army, which had been founded to fight in World War I and was disbanded in 1920.

The first commissioned officers of the Army of the United States were appointed from the Regular Army. The standard practice that these officers held a "permanent rank" within the Regular Army as well as a higher "temporary rank" while serving in the Army of the United States. A typical situation might be a colonel in the AUS holding the permanent rank of captain in the Regular Army. Another term for the AUS was "Theater Rank," held by officers deployed to the European Theater or serving in the Pacific.

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