The U.S. Army on Alcatraz: Fort, Prison and Laundry

Long before gangsters were sent to Alcatraz, the island belonged to the U.S. Army. This page follows that earlier chapter, from gold rush fortifications to a military prison and a laundry, and explains why the Army gave the island up.

A fort for the Golden Gate

In the 1850s the Army began fortifying Alcatraz as one corner of a triangle of forts guarding the Golden Gate and protecting San Francisco, through which gold from the California gold rush was shipped. It was an active military post and part of the coastal defences.

The island looks quite different today from how the soldiers found it. The plan called for turning it into a two-level plateau by blasting away the hillside and levelling the parade ground out to roughly where the later cellhouse library stood, then lowering the citadel level. They never went that far, but the “battleship” profile and the deep cut into the cliffs that produced the parade ground were still a major construction effort. The purpose was defensive: a level, lowered upper tier could hold large mortars.

During the Civil War of the 1860s, Union supporters in California worried about Confederate raids, since the gold still arriving from the Sierra foothills and the businesses it had created would tempt a cash-strapped enemy.

Technology then overtook the island. Rifled artillery, which spun missile-shaped shells with far greater range and accuracy, replaced smooth-bore guns that fired round balls. Early in the war it was used against Fort Pulaski in Georgia, which was breached in hours rather than days. With such guns, the critical point of defence became the entrance to the bay, where enemy ships could be engaged before passing the Golden Gate. Alcatraz was modernised, but attention shifted to Fort Point and the huge excavation project was dropped.

Did it ever fight?

No, and the record of the period suggests that may have been fortunate. During the Centennial celebrations of July 1876, an old schooner loaded with explosives and coal oil was anchored in the bay for a demonstration, watched by an estimated 50,000 people on San Francisco’s hills. Naval vessels opened fire shortly before noon, and not one shot hit directly. In the end a small boat had to approach under cover of smoke to set the schooner alight. On Alcatraz that day, the cannon demonstration began just as poorly against a target at Lime Point, though the guns eventually found their mark.

The first prison

In the wartime rush of the 1860s, local commands found Alcatraz a convenient place to hold soldiers considered unfit for ordinary duty. It was out of the way, and the cold, fast water made security a minor concern.

The arrangement worked so well that the island was named the Pacific Branch, U.S. Military Prison in 1907 and the Pacific Branch, U.S. Disciplinary Barracks in 1915. It was the first time the Army had set aside one location as a regional prison; before that every command ran its own stockade.

The prisoner mix was varied: stowaways found on foreign ships, Civil War privateers, captives from Indian campaigns in the West and even a German diplomat during World War I, alongside disloyal officers, conscientious objectors, deserters and ordinary offenders. At first they were held in a guardhouse above the moat in the sallyport. A wooden building followed behind it, later replaced in brick, and serious cases went to the basement of the citadel. Around 1900, the Spanish-American War caused a jump in numbers, building fortifications was set aside, and buildings were hurriedly put up for inmates. Eventually the island served solely as a military prison.

Why the Army left

By the early 1930s the Army judged that the arrangement no longer worked. The First World War was long over and the service was shrinking. Islands are costly places to run prisons, because supplies arrive by boat, power must be generated locally and the garrison is cut off from its command. Money was scarce during the Great Depression, and the War Department, having already spent millions on the island, wanted another agency to take it over.

The Department of Justice was looking for a high-security site and faced the same budget limits. Island isolation was attractive, but the fact that the transfer cost nothing weighed heavily. Even so, the Bureau of Prisons could get approval to replace the bars in only half of the cellblocks.

Army prison versus federal penitentiary

Military prisoners were expected to work through their duty hours as soldiers would. For much of the period they broke large rocks with sledgehammers to clear room for development. They built retaining walls, shaped hillsides and planted vegetation on the barren rock. They also built the cellhouse, finished in 1912. Later, they turned to laundry work, because the Army decided the island was a good central location for a laundry serving the bay area. That work continued after the Army had left.

When Justice took control in 1934, the emphasis moved from hard labour to tight security. The new penitentiary kept the Army laundry contract and 32 of the toughest military inmates. Officials then searched other federal prisons for the most disruptive and escape-prone men and sent them by train. They lived in the same cells, in the same cellhouse, but life for these men was very different from that of the deserters and petty offenders held before.