Origins
The United States Army traces its founding to June 14, 1775, when the Continental Congress authorized the raising of ten companies of riflemen to support the New England militia forces besieging British-held Boston. The following day, Congress appointed George Washington as Commander in Chief of the Continental Army, beginning a tradition of civilian control over the military that remains foundational to American governance. This force fought the Revolutionary War through 1783, though it was largely disbanded after independence.
The early Republic maintained deep suspicions of standing armies, viewing them as tools of tyranny. The Army remained minuscule—often fewer than 1,000 soldiers—with national defense entrusted to state militias. The War of 1812 exposed the inadequacy of this system: militia forces proved unreliable, and the British burned Washington, D.C. Subsequent decades saw gradual professionalization, including the establishment of West Point (1802), the creation of the General Staff concept, and reforms following each major conflict.
The Civil War transformed the Army into a massive industrial-age force of over one million soldiers, introducing conscription, corps organization, and strategic logistics on an unprecedented scale. The post-war Army shrank dramatically but maintained frontier garrisons and fought the Indian Wars through 1890. The Spanish-American War (1898) and Philippine-American War demonstrated the need for further reform, leading to the Root Reforms of 1903 that established the Army Chief of Staff and modern staff system.
Structure & Function
The modern Army operates under the Department of the Army, headed by a civilian Secretary of the Army and the uniformed Chief of Staff of the Army. The Army is organized into the Regular Army (active duty), Army National Guard (state-based but federally deployable), and Army Reserve. Total strength approximates 1,000,000 personnel across all components, making it the largest branch of the US armed forces.
The Army’s operational structure centers on divisions and corps for large-scale operations, with brigade combat teams as the primary deployable units. Three types of brigade combat teams exist: infantry, Stryker (medium-weight wheeled vehicles), and armored. Supporting brigades provide aviation, artillery, engineer, logistics, and other capabilities. Army Special Operations Command oversees Special Forces (Green Berets), Rangers, psychological operations, and civil affairs units.
The Army maintains four major commands for force generation: Training and Doctrine Command develops doctrine and trains soldiers; Forces Command prepares units for deployment; Army Materiel Command manages equipment and logistics; Army Futures Command drives modernization. Geographic combatant commanders—not the Army—direct units in combat, following the Goldwater-Nichols framework. The Army’s core competencies include combined arms maneuver, wide-area security, armored warfare, airborne and air assault operations, and sustained land campaigns.
Historical Significance
The United States Army has fought in every American war and shaped the nation’s territorial expansion, international position, and domestic development. The Army conquered the continent through the Indian Wars and Mexican-American War, acquired overseas territories in 1898, and deployed millions of soldiers in two world wars. American ground forces proved decisive in defeating Nazi Germany and Imperial Japan, establishing the United States as a global superpower.
During the Cold War, the Army maintained large forces in Europe and Korea as deterrents against communist expansion, while fighting major wars in Korea and Vietnam. The latter conflict, with over 58,000 American deaths and ultimate strategic failure, triggered fundamental reforms in training, doctrine, and the all-volunteer force. The AirLand Battle doctrine of the 1980s, validated in the 1991 Gulf War, demonstrated recovered effectiveness through precision weapons, maneuver warfare, and joint operations.
The Army’s influence extends beyond combat. The Corps of Engineers has shaped American infrastructure since 1802, building harbors, dams, and flood control systems. Army research produced foundational computing technologies and medical advances. The GI Bill, providing education benefits to veterans, transformed American higher education and social mobility. Military service has served as a path to citizenship, social integration, and advancement for immigrant and minority communities throughout American history.
Key Developments
- 1775: Continental Congress establishes the Continental Army; Washington appointed commander
- 1783: Army largely disbanded after Revolutionary War victory
- 1802: United States Military Academy established at West Point
- 1861-1865: Civil War; Army grows to over one million soldiers
- 1898: Spanish-American War; Army acquires overseas responsibilities
- 1903: Root Reforms establish General Staff and modern organization
- 1917-1918: American Expeditionary Forces deploy to Europe; two million soldiers serve
- 1941-1945: World War II; Army grows to 8.3 million soldiers
- 1947: Army Air Forces become independent Air Force
- 1950-1953: Korean War; Army suffers 36,000 deaths
- 1965-1973: Vietnam War; 2.7 million serve; 47,000 Army deaths
- 1973: Transition to all-volunteer force
- 1991: Gulf War validates AirLand Battle doctrine
- 2001-2021: Continuous combat deployments in Afghanistan and Iraq
- 2024: Army Futures Command drives modernization for great power competition