The Commanding General of the United States Army was the title given to the service chief and highest-ranking officer of the United States Army, prior to the establishment of the Chief of Staff of the United States Army in 1903. During the American Revolutionary War (1775–1783), the title was Commander-in-Chief of the Continental Army. In 1783, the title was simplified to Senior Officer of the United States Army. In 1821, the title was changed to Commanding General of the United States Army. The office was often referred to by various other titles, such as "Major General Commanding the Army" or "General-in-Chief".

The chief of staff of the Army (CSA) is a statutory position in the United States Army held by a general officer. As the highest-ranking officer assigned to serve in the Department of the Army, the chief is the principal military advisor and a deputy to the secretary of the Army. In a separate capacity, the CSA is a member of the Joint Chiefs of Staff and, thereby, a military advisor to the National Security Council, the secretary of defense, and the president of the United States. The CSA is typically the highest-ranking officer on active duty in the U.S. Army unless the chairman or the vice chairman of the Joint Chiefs of Staff are Army officers.