Department (United States Army) Explained

Department is an organizational term used by the U.S. Army, mostly prior to World War I, to describe named geographical districts created for control and administration of installations and units. In 1920, most of the named departments were redesignated as numbered Corps Areas. However, the Hawaiian, Panama Canal, and Philippine Departments retained their old names. In 1939, the Puerto Rican Department was created and in May 1941 the Panama Canal and Puerto Rican Departments were combined as the Caribbean Defense Command, although each was still referred to as a department.

1800s

War of 1812

The United States Army was divided into nine military districts by the War Department General Order, of 19 March 1813. They were increased to ten on 2 July 1814 but reduced to nine by consolidation of the 4th and 10th Military Districts in January 1815. Military districts were abolished, 17 May 1815.

1815–21

At the end of the War of 1812, Military districts were superseded by ten Military Departments, divided equally between Divisions of the North and South, 17 May 1815.

1821–1837

Reorganization of the Army into Eastern and Western Departments, May 1821.

1837–1844

From 1837 to 1842, some of the Departments were subordinated to the Eastern and Western Divisions.

1844–1848

The Eastern and Western Divisions were not restored until 1853.

1848–1853

All departments were subordinated under one of three Divisions.

1853–1861

After 31 October 1853 the division echelon was eliminated and the six western departments consolidated into four (Departments of Texas, New Mexico, the West, and the Pacific), whose department commanders employed their troops as they saw fit. The system returned to six departments in 1858 when the Department of Utah was created in January, and the Department of the Pacific split into the Departments of California and Oregon in September.

1861–1865 Civil War

During the American Civil War, a department was a geographical command within the Union's military organization, usually reporting directly to the War Department. Many of the Union's departments were named after rivers, such as the Department of the Potomac and the Department of the Tennessee. The geographical boundaries of such departments changed frequently, as did their names. As the armies became larger Departments began to be subordinated to Military Divisions, and the Departments were often sub divided into Districts and from 1862, Subdistricts. Much information on Civil War departments can be found in Eicher & Eicher, Civil War High Commands.

1865–67

Military Reconstruction from 22 March 1867

1868–1904

1898–99 Spanish–American War, Philippine Insurrection, Moro Rebellion

1900s

1904–1911

The Army Departments were reorganized under new Divisions until 1907, when the Division echelon was disbanded.

Western Division (United States Army) 1911–1913

The Departments where again organized under new Divisions.

"Stimson Plan" 1913 – 1 May 1917

1 May 1917 – 1920

See also

References