The Port Chicago disaster was a deadly munitions explosion in Port Chicago, California, United States. Munitions detonated while being loaded onto a cargo vessel bound for the Pacific Theater of Operations, killing 320 sailors andcivilians and injuring 390 others. Most of the dead and injured were enlisted African-American sailors.

A month later, continuing unsafe conditions inspired hundreds of servicemen to refuse to load munitions, an act known as thePort Chicago Mutiny. Fifty men—called the "Port Chicago 50"—were convicted of mutiny and sentenced to long prison terms. Forty-seven of the 50 were released in January 1946; the remaining three served additional months in prison.

On the night of 17th July 1944, two transport vessels loading ammunition at the Port Chicago (California) naval base on the Sacramento River were suddenly engulfed in a gigantic explosion. The incredible blast wrecked the naval base and heavily damaged the small town of Port Chicago, located 1.5 miles away. Some 320 American naval personnel were killed instantly. The two ships and the large loading pier were totally annihilated. Several hundred people were injured, and millions of dollars in property damage was caused by the huge blast. Windows were shattered in towns 20 miles away, and the glare of the explosion could be seen in San Francisco, some 35 miles away. It was the worst home-front disaster of World War II. Officially, the world's first atomic test explosion occurred on 16th July 1945 at Alamogordo, New Mexico; but the Port Chicago blast may well have been the world's first atomic detonation, whether
accidental or not. 

320 sailors were killed
instantly!

 The E. A. Bryan, the ship which exploded at Port Chicago, was a 7,212-ton EC-2 Liberty ship commanded by Captain John L. M. Hendricks of San Pedro, California, and operated by Oliver J. Olson & Co., San Francisco. It was built and launched at the Kaiser Steel shipyard in Richmond, California, in March 1944. She made a maiden voyage to the South Pacific and then was ordered into the US Navy's Alameda Shipyards where the five-ton (10,000-pound maximum load) booms and gear on the no. 1 and no. 5 holds were removed and replaced with 10-ton booms and gear. It then docked at Port Chicago on 13th July 1944. At 8:00 a.m. on 14th July, naval personnel began loading ammunition.

The E. A. Bryan had been moored at Port Chicago for four days, taking on ammunition and explosives night and day. Some 98 men of Division Three were hard at work loading the Bryan, and by 10:00 p.m. on 17th July the ship was loaded with some 4,600 tons of munitions including 1,780 tons of high explosives.

The second ship, the Quinalt Victory, was brand new; it was preparing for its maiden voyage. The Quinalt Victory had moored at Port Chicago at about 6:00 p.m. on the evening of 17th July. Some 102 men of the Sixth Division, many of whom had only recently arrived at Port Chicago, were busy rigging the ship in preparation for loading of ammunition which was
due to begin by midnight.