The United States Army traces its origin to June 14, 1775, when the Continental Congress created the Continental Army to fight Great Britain in the Revolutionary War. Many official U.S. military and museum sources treat this 1775 date as the Army’s “birthday,” even though a later act of Congress on September 29, 1789, organized the early permanent federal Army after the Revolution.

Core dates

  • June 14, 1775 – Establishment of the Continental Army by the Second Continental Congress, considered the formal beginning of the U.S. Army and celebrated annually as the Army’s birthday.
  • September 29, 1789 – The new U.S. Congress passed legislation creating a permanent national army under the Constitution, building on forces that had continued from the Revolutionary era.

Quick context

The Continental Army formed in 1775 as a unified colonial force, replacing ad hoc militias and preparing for large-scale war with Britain. After victory and the war’s end, most of that force was disbanded, and a much smaller standing army was later formalized under the new federal government in 1789.