World History Maps Interactive Historical Atlas of the Civil War, detail page for:

The Pacific, US Army Department Jan 1, 1861 - after Jun 25, 1865

US Dept. of The Pacific created merging Depts. of California and Oregon, Jan 15, 1861
Albert S. Johnson Commander, Jan 15, 1861 - Feb 23, 1861
Edwin V. Sumner Sr. Commander, Mar 23, 1861 - Oct 20, 1861
George Wright Temp Commander, Oct 20, 1861 - Nov 19, 1861
George Wright Commander, Nov 19, 1861 - May 21, 1864

Former US Dept. of Utah area absorbed by Dept. of the Pacific, Aug 6, 1862

Bear River, battle, Jan 29, 1863

Irvin McDowell Commander, May 21, 1864 - after Jun 25, 1865

Arizona transferred from US Dept. of New Mexico to Dept. of the Pacific, Jan 20, 1865