Spanish explorer Lt. Juan Manuel de Ayala maps San Francisco Bay and names an island "de los alcatraces".
California becomes U.S. property at the end of the Mexican-American War. Gold is discovered along the American River and the Gold Rush begins.
A joint Army and Navy commission recommends a Triangle of Defense to guard San Francisco Bay. President Fillmore signs an Executive Order reserving lands around San Francisco Bay, including Alcatraz, for "public purposes."
The Alcatraz lighthouse begins service as the first lighthouse on the Pacific Coast.
Capt. Joseph Stewart and 86 men of Company H, Third U.S. Artillery take command of Alcatraz.
Fort Sumter is attacked by Confederates and the Civil War begins. Col. Jonhston prepares San Francisco defenses, then resigns to serve the Confederacy.
J.M. Chapman, a Confederate privateer ship, is seized and its crew is arrested and imprisoned on Alcatraz.
Capt. William Winder authorizes Alcatraz to fire a blank shot at HMS Sutlej.
Lower prison, a temporary wooden structure, is built. Soon other prison structures are added on to it.
Capt. Winder authorizes Bradley and Rulofson to photgraph Alcatraz and sell prints, which are later confiscated by the War Department.
Alcatraz troops are sent to San Francisco to preserve peace and prevent rioting after President Lincoln's assassination. Alcatraz cannons fire the official mourning for the dead president.
Major George Mendell designs plans for earthwork defenses on Alcatraz.
Centennial Great Sham Battle proves Alcatraz defenses are no longer adequate.
Nineteen members of the Hopi Tribe are imprisoned on Alcatraz for resisting the policy of forced education of their children and land alotment programs contrary to their beliefs.
Spanish-American War results in prison overcrowding at Alcatraz.
Upper prison (Alcatraz's second prison) is built on the Parade Ground.
Alcatraz is designated as the "Pacific Branch, U.S. Military Prison".
The new cellhouse (Alcatraz's third prison which still stands today), built with convict labor, is completed and prisoners move in.
Alcatraz is renamed the "United States, Disciplinary Barracks".
Alcatraz is transferred to the Federal Bureau of Prisons. 32 of the worst military prisoners remain on the island in civilian custody.