Pacific Coast Theater of the American Civil War

The Pacific Coast Theater of the American Civil War consists of major military operations in the United States on the Pacific Ocean and in the states and Territories west of the Continental Divide. The theater was encompassed by the Department of the Pacific that included the states of California, Oregon, and Nevada, the territories of Washington, Utah, and later Idaho.

The operations of Union volunteer troop detachments, primarily from California, some from Oregon, and a few companies from Washington Territory, were directed mostly against Indians in the theater. Union and Confederate regular forces did not meet directly within the Pacific Department except in New Mexico Territory. However, operations were directed against Confederate irregulars in California and strong garrisons were placed in Southern California and southern New Mexico Territory to control the region which had strong secessionist sympathies.

Confederate States Navy warships operated in the Pacific Ocean, but the naval operations did not succeed in interrupting commerce to the Eastern United States. The last of these commerce raiders, CSS Shenandoah, fired the last shot of the War in the Bering Sea off the coast of Alaska. Attempts by the Confederacy to buy or seize ships for commerce raiding on the West Coast were thwarted by alert Union officials and the Pacific Squadron.

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