While no battles were fought within the state of California, there were a number of Civil War sites in California including, forts, camps, and prisons.

While no battles were fought within the state of California, there were a number of Civil War sites in California including, forts, camps, and prisons. This was one of the facts about California during the Civil War. There were numerous camps and forts utilized by the Union Army and pro-Union state militias all around California. The Drum Barracks, one of these numerous forts, acted as the command center for the Union Army in Southern California and Arizona Territory.

Over 17,000 volunteers eventually came from California, and the Drum Barracks served as the departure point for over 8,000 of those soldiers for the Southwest. One of the few Civil War forts left intact in California is the Drum Barracks, which is still standing today. The notorious Alcatraz Federal Penitentiary is arguably the most well-known Civil War building in California. During the American Civil War, Alcatraz housed captured Confederates before becoming a Federal Penitentiary.