Pacific Division (United States Army)

Pacific Division of the U. S. Army was one of its superior administrative organizations that existed during the early 19th century and for a short time in the early 20th century.
Pacific Division 1848–1853.
The first Pacific Division of the U.S. Army was created on October 10, 1848, as the Army reorganized its administration for the new territories acquired during the Mexican–American War. 10th Military Department (California) and 11th Military Department (Oregon Territory) were subordinated to the new Division that had its headquarters at Monterey. In June 1849 division headquarters moved to the California, for a month then moved to Benicia and the Benicia Arsenal in the upper San Francisco Bay in July 1849.
On May 17, 1851, the Army merged Military Departments 10 and 11 into the Pacific Division as the Army again reorganized its administration on the West Coast. Both of those military departments merged into the Pacific Division ceased to exist. Division headquarters directly administered affairs in California and Oregon Territory. On June 15, 1852, Pacific Division headquarters was moved from Benicia to the San Francisco.
On October 31, 1853, the Pacific Division was replaced by the Department of the Pacific, with headquarters at San Francisco. It was created when the Army abandoned the system of divisions and numbered departments, establishing departments having a descriptive name, and reporting directly to Army Headquarters.
Pacific Division, 1904–07.
Several Departments were again organized under new Divisions in 1903. The previous Division of the Pacific (1869-91) was re-established and formally stood up in 1904 as the Pacific Division with subordinate or related commands, including the Department of California (to include the Hawaiian Islands) and the Department of the Columbia. The Pacific Division was headquartered at Fort Mason, San Francisco. By the end of 1907, the War Department, under Secretary of War William Howard Taft from February 1, 1904 – June 30, 1908, had eliminated the echelon of administrative units called Divisions and subsequently the Pacific Division that same year.