Department of the Pacific

The Department of the Pacific or Pacific Department was a major command (Department) of the United States Army during the 19th century.

The Department of the Pacific was created on October 31, 1853, at San Francisco, California, replacing the older Pacific Division, (1848-53) and abolishing the existing 10th (California) and 11th (Oregon) Departments, consolidating them within the new Department. The department reported directly to the headquarters of the Army in Washington, D.C.. It oversaw the military affairs in the country west of the Rocky Mountains (California, Oregon Territory, and Washington Territory), except for the Utah Territory and the Territory of New Mexico east of the 110th meridian west, (thus including most of modern Arizona and southern Nevada).

On September 2, 1854, the headquarters was moved to Benicia Barracks, in Benicia, California.

From 1855-57 the Puget Sound District was organized.

In January 1857, the headquarters again returned to San Francisco.

On January 14, 1858, the Utah Territory was placed within the Department but soon removed into the Department of Utah, in 1858, that remained until 1861.

On September 13, 1858, the Department of the Pacific was disbanded, replaced by two new departments: the Department of California and the Department of Oregon. The Department of California included the territory west of the Rockies, the Umpqua and Rogue River districts in Oregon, Utah and New Mexico. The Department of Oregon included the Oregon and Washington Territories.

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