Civil War at Alcatraz


The National Park Service is commemorating the 150th anniversary of the Civil War (1861 – 1865.) We acknowledge this defining event in our nation’s history and its legacy in continuing to fight for civil rights, or as Abraham Lincoln said in his Gettysburg Address, “that this nation….shall have a new birth of freedom.” To learn more about the National Park Service’s Sesquicentennial Commemoration of the Civil War, please visit The Civil War: 150 Years page.


Early Military Planning for Alcatraz

After the U.S. government took control of California from the Republic of Mexico in the late 1840s, it identified Alcatraz Island as a place of great strategic military value. Located in the middle of the bay, the island offered 360-degree military protection. The Army’s Corps of Engineers designed a "Triangle of Defense", planning to install guns on Alcatraz, Fort Point and Lime Point (ultimately never constructed) to guard the entrance of San Francisco Bay. The 1848 discovery of gold in California catapulted the territory to the center of national attention and prompted the need for additional military protection. To learn more about Civil War events and personalities in California and the San Francisco Bay Area, please visit the Civil War at Golden Gate page.


Building Fortress Alcatraz

Originally, the army’s plans for developing the fort at Alcatraz Island was part of the “Third System of U.S. military fortifications” identified as the third generation of American forts. Traditionally, the military plan for constructing such a fort was to select a strategic location, cut the site down to sea level and then construct a multi-tiered masonry fort with thick stone and brick walls. However, the nature of Alcatraz Island’s geology did not lend itself well to this traditional military plan. Because of the island’s natural height and isolation, the site already had great strategic potential. Instead of cutting the rock and soil down to sea level, the Army Corp of Engineers incorporated Alcatraz’ rugged topography into its defense plan.

Army construction started on Alcatraz in 1853. Blasting at the rock and laying brick and stone, laborers created steep walls around the island. Behind the walls, the army placed cannon at the north, south, and west sides to enable gunfire at incoming enemy ships. When the work was finished, the army had constructed emplacments for 111 cannons that encircled the island. To the north and south, masonry towers jutting out from the island midway between gun batteries held smaller guns to protect the sides of the island. For more information on the guns of Fort Alcatraz, please visit the Alcatraz fortifications page.

Crowning the island near the lighthouse (the first built on the Pacific coast in 1854) was a defensive barracks called the Citadel. The Citadel was the final defense if the island was attacked. Constructed of sturdy brick walls with rifle-slit windows, the two upper stories provided living quarters, and the basement featured kitchens, dining halls, and storage for food, water and ammunition. Soldiers entered the Citadel by crossing a drawbridge over a deep dry moat surrounding the building. The Citadel could hold 100 men during peacetime and double that number under attack. By rationing provisions, troops could withstand a four-month siege. With the army’s state-of-the-art military construction, Alcatraz Island became the most powerful of all Pacific Coast defenses.

Nature seems to have provided a redoubt for this purpose in the shape of Alcatrazes [sic] Island…..situated abreast the entrance directly in the middle of the inner harbor, it covers with its fire the whole of the interior space lying between Angel Island to the North, San Francisco to the South, and the outer batteries to the West.... a vessel passing directly to San Francisco must pass within a mile.

- The Board of Engineers for the Pacific Coast, 1852


The Evolution of Alcatraz as a Military & Civilian Prison

Though Alcatraz is now famous for its role as a federal prison, its history as a holding place for criminals began before the Civil War. The army first used the guardhouse’s basement cell room in 1859 to contain soldiers who had committed crimes. Because of the island’s escape-resistant location in the middle of San Francisco Bay, other army posts began to send their hardcore soldier prisoners to Alcatraz for safekeeping. By 1861, the government designated Fort Alcatraz as the official military prison for the entire Department of the Pacific.

It was during the Civil War that the military began to house a different kind of prisoner. When President Lincoln suspended the writ of habeus corpus in 1863, the judicial system could arrest individuals and imprison them without trial in a court of law. The Union government in San Francisco now used the Alcatraz guardhouse to imprison private citizens, accused of treason, as well as soldiers. At this time, treason was broadly defined to encompass any pro-Confederate or anti-Union sentiment, from rejoicing in the Union’s loss of a battle, refusing to take an oath of loyalty to the Union, or recognizing the Confederate States of America, to plotting or privateering for the Confederate cause. Many local politicians and citizens, whose loyalty to the Union was suspect, were arrested and jailed on Alcatraz to serve time. These prisoners could be detained without a trial and despite a lack of sufficient evidence of their crimes.

historic photo of Civil War soldier at mounted Fort Alcatraz canon overlooking San Francisco Bay
A Fort Alcatraz soldier stationed at a mounted Rodman gun, one of the scores of heavy guns mounted in barbette batteries that ringed the island in all directions.

Photo courtesy of Bancroft Library, PARC, GGNRA

Fort Alcatraz’ Military Significance

By 1859, as the country was heading towards a civil war, Fort Alcatraz stood as the only permanent completed military fortification on San Francisco Bay (and west of the Mississippi River.) Unfortunately, the “Triangle of Defense” was not yet operational. Fort Point was still under construction and would not be finished until 1861 and the army’s Lime Point construction had stalled due to land ownership issues. The plans for forts on Angel Island, Yerba Buena Island and Point San Jose were even farther behind and only existed as drawings on engineers’ maps.

In contrast, the army continued to work on Alcatraz throughout 1860 and 1861, expanding and improving the island’s existing fortifications. The military also used the island as a training ground for soldiers. New troops continually arrived on the island, underwent training, and departed for other assignments. With many new enlistees, the military personnel on Alcatraz increased to over 350 by the end of April 1861. The army slowly increased the number of men assigned to Alcatraz throughout the Civil War, reaching a high point of 433 men in early 1865. The army shipped most of these soldiers out to the Southwestern frontier; however, some were sent to battlefields in the East.


Protecting San Francisco from Enemies of the Union

From the very beginning of the Civil War, the government considered Fort Alcatraz to be one of the strongest and most formidable military fortifications in the entire United States. As rumors came to light that Southern sympathizers were plotting to separate San Francisco and its wealth from the Union, Fort Alcatraz’s coastal defense position became even more significant. A series of events at Fort Alcatraz illustrated both some admirable aspects of war as well as some chilling ones. During the Civil War, the country’s new division pitted brother against brother, turning former friends and allies into enemies. Fort Alcatraz became a political backdrop, illustrating how war and rumors called certain people’s military allegiance into question.


Colonel Albert Sidney Johnston


I have heard foolish talk about an attempt to seize the strongholds of government under my charge. Knowing this, I have prepared for emergencies, and will defend the property of the United States with every resource at my command, and with the last drop of blood in my body. Tell that to our Southern friends!

- Colonel Albert Sidney Johnston,
Commander of the Department of the Pacific,
U.S. Army, 1861


Colonel Albert Sidney Johnston’s role during the Civil War tells a compelling story about duty and loyalty during wartime. Johnston, born in Kentucky and raised in Texas, served in three different armies: the Texas Army, the United States Army and the Confederate States Army. Jefferson Davis, the President of the Confederate States, considered Johnston to be the finest military officer in the United States. By January 1861, while still a member of the Union Army, Johnston was rewarded with the appointment of Commander of the Department of the Pacific in California; one of his many responsibilities included the protection of Fort Alcatraz.

Despite Johnston’s great military experience and leadership capabilities, his southern roots and association with Jefferson Davis undermined the public’s faith in his commitment to defend the Golden Gate from potential southern attack. Many San Francisco citizens who questioned his loyalty spread rumors that local confederates had approached him to seek his help in attacking the city.

historic  image of Albert Sidney Johnston in military dress
Colonel Albert Sidney Johnston


However, while Col. Johnston served the Union Army, he did faithfully fulfill his duty to calm the threat of war locally and to protect San Francisco. Fearing an attack on Benicia Arsenal, he ordered the transfer of rifles and ammunition to Alcatraz for safekeeping. Johnston also ordered the acceleration of Fort Point’s construction and demanded that they position its first mounted guns to defend against attacks from the city. Col. Johnston directed those under him to maintain calm among San Francisco’s civilian population and provided additional troops to defend their posts against any attempts to seize them.

While the Union Army was confident that Col. Johnston would not do anything dishonorable, they feared that he was still too vulnerable to potential Southern influence. In April 1861, Col. Johnston was relieved of his post. After returning to the South, Johnston accepted a commission as general in the Confederate Army and died at the battle of Shiloh as one of the greatest heroes of the Confederacy.


The J.M. Chapman

The first threat to California's security occurred in March, 1863. The Union government learned that a group of Confederate sympathizers planned to arm a schooner, the J.M. Chapman, use it to capture a steamship which would raid commerce in the Pacific, and threaten to blockade the harbor and lay siege to the forts. However, the Confederates' plans were thwarted when their ship captain bragged about their scheme in a tavern. On the night the Chapman was to sail, the U.S. Navy seized the ship, arrested the crew and towed the Chapman to Alcatraz, where an inspection revealed cannons, ammunition, supplies, and fifteen hiding men. One of these men, a prominent San Franciscan, had papers signed by Confederate President Jefferson Davis ensuring him an officer's commission in the Confederate Navy as a reward for this daring plot.

Rather than becoming Confederate heroes, the three ringleaders were arrested as traitors and confined in the Alcatraz guardhouse basement during the investigation. After a quick trial and conviction for treason, they were spared ten years imprisonment on Alcatraz by a pardon from President Lincoln. The Unionists in San Francisco were shocked by the incident and feared that other Confederates were plotting in their midst.


H.M.S. Sutlej

In October 1863, an unidentified warship entered San Francisco Bay. Because there was no wind, the flag hung limp and men in rowboats towed the ship. The ship did not head toward the San Francisco docks but instead, made way towards Angel Island and the army arsenal and navy shipyard. The commanding officer at Alcatraz had a duty to ensure that no hostile warship entered the bay.

Captain William A. Winder, Post Commander, ordered the Alcatraz artillery to fire a blank charge as a signal for the ship to stop. The rowboats continued pulling the ship. Winder then ordered his men to fire an empty shell toward the bow of the ship, a challenge to submit to the local authority. The ship halted and responded with gunfire, which Winder confirmed was a 21-gun salute. Through the smoke, the Alcatraz troops could finally see the British flag waving on the H.M.S. Sutlej, flagship of Admiral John Kingcome. Alcatraz responded with a return salute.

Soon messages were exchanged rather than gunfire. As Commander-in-Chief of the Royal Navy's Pacific Squadron, Kingcome wrote that he was displeased at his reception in San Francisco. Captain Winder explained his actions by saying, "The ship's direction was so unusual I deemed it my duty to bring her to and ascertain her character." The U.S. Commander of the Department of the Pacific supported Winder and replied that Kingcome had ignored the established procedures for entering a foreign port during war. Winder later received a letter of gentle reminder to act cautiously. Many San Franciscans applauded Winder's actions knowing that Great Britain favored the Confederacy.


The Bradley and Rulfolson Photography Controversy

black & white contact sheet showing double images of Alcatraz views
Fortunately, eight of the fifty Bradley & Rulfolson photos have been recently found. A descendent of a Civil War soldier station at Alcatraz  donated them to the City of Sacramento. (photo circa 1864)


Out of pride for Alcatraz’ grand fortifications, the Fort Alcatraz commander Captain Winder authorized noted commercial photographers Bradley and Rufolson to take photos of the island in the summer of 1864. The photographers were very thorough, capturing fifty different views of the island, including the Citadel, the dock, the soldiers’ barracks and every road and gun battery on the island. In order to offset the photographers’ expenses, prints of the photographs were to be made into portfolios and sold to the public for $200 a set.

However, the War Department in Washington, D.C. did not commend Winder for his initiative and pride in his post, but rather questioned Winder's motives because his father was an officer in the Confederate Army. The Secretary of War ordered all the prints and negatives to be confiscated as a threat to national security. Later, Captain Winder humbly requested a transfer to Point San Jose, a small defense post on the mainland, later renamed Fort Mason.


The Winder Family: One of Many Divided Families during the Civil War

Besides dividing the nation, the Civil War sometimes divided families, especially in the border states of Maryland, Missouri and Kentucky where slaveholding was legal but Union sentiment was also strong. The family of Captain William A. Winder was one example, and their commitment to the Confederacy cast the pall of suspicion on the commander of Fort Alcatraz.

One local newspaper stated that while commanding Alcatraz, Captain Winder “was feeding the rebel prisoners held there on the fat of the land and off from silver plates.” This printed exaggeration was a particularly charged assertion because his father, Brigadier General John H. Winder, was vilified in the North as the Confederate officer in charge of prisoner-of-war camps for Union Soldiers, camps notorious because of near-starvation rations and unhealthy conditions.

Two of Captain William Winder’s half-brothers were also captains in staff positions for the Confederate Army, while his second cousin, Brigadier General Charles S. Winder died in combat at the head of the famous Stonewall Brigade, an elite unit once commanded by Stonewall Jackson himself!

Given the number of Confederates in Captain Winder’s family, it was no wonder that criticism mounted in the wake of the Bradley and Rulfolson photography fiasco to the point that that Alcatraz garrison was reinforced by a contingent whose officer-in-charge outranked Winder. Chastened and humbled, Captain Winder sought transfer and the army reassigned him to the command of the Fort Mason post for the remainder of the war. Shortly thereafter, he resigned his commission. Nevertheless, in later years, Winder received testimonials for his loyal service from a number of influential officers, including the Commander of the Department of California, Brigadier General George Wright, who wrote, “I was fully convinced of his loyalty to the Government. At the frequent inspections I made of Alcatraz during his command, I always found everything in the most perfect order and satisfactory condition. His system of alarm signals to prevent surprise, and general preparations to meet any emergency, evinced a thorough knowledge of his duty and responsibility of the most important defense of the harbor and city of San Francisco.” (from a report in an 1894 Congressional Edition)


The End of the War

As the Civil War lingered on and the Union seemed likely to win, the U.S. Army was willing to devote more resources to the Pacific Coast. The end of the bloodshed came in sight when Confederate General Robert E. Lee surrendered his army to General Ulysses S. Grant at Appomattox Court House, Virginia on April 9, 1865. Unlike the news of the beginning of the war, which took twelve days to reach California on horseback, the news of its end quickly reached San Francisco via telegraph. The city erupted in great celebration, with citizens cheering in the streets and guns booming from many of the forts around the bay. Less than a week later, on April 15th, another telegraph came bringing less joyous news: this telegraph told the city of President Abraham Lincoln’s assassination. This time the city descended into chaos. Pro-Union mobs ransacked the offices of a local Confederate newpaper and attacked many citizens thought to be pro-Confederate. The military ordered artillerymen from Fort Alcatraz into the city to maintain order, prevent rioting, and punish anyone was bold enough to rejoice in the tragedy. Confederate sympathizers throughout California who celebrated Lincoln’s death, were arrested and imprisoned on Alcatraz. During the city’s official mourning period, Alcatraz’ batteries were given the honor of sending out a half-hourly cannon shot over the bay as a symbol of the nation’s grief.


To learn more about Civil War events in California and the San Francisco Bay Area, please visit the Civil War at Golden Gate page.

To learn more about how Californian historical events and personalities played a role in the Civil War, please visit the California Role in the Civil War page.

To learn more about Point San Jose military reservation (later Fort Mason), please visit the Civil War at Fort Mason page.

For More Reading:

Alcatraz at War by John Martini (2002)

Fortress Alcatraz; Guardian of the Golden Gate by John A. Martini (2004)

Artillery at the Golden Gate by Brian B. Chin

For other Alcatraz-related books, please visit the Parks Conservancy online bookstore.

Last updated: March 19, 2015

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