|Oliver Albert O'Brien|
|Died||October 1, 1894 (aged 54–55)|
|Place of burial||Oak Hill Cemetery, Gloucester, Massachusetts|
|Service/branch||United States Navy|
|Rank||Acting master's mate|
|Unit||USS John Adams[nb 1]|
|Battles/wars||American Civil War|
|Awards||Medal of Honor|
Oliver Albert O'Brien (1839 – October 1, 1894) was a Union Navy sailor in the American Civil War and a recipient of the U.S. military's highest decoration, the Medal of Honor, for his actions during the capture of a blockade runner.
Born in 1839 in Boston, O'Brien was still living in that city when he joined the Navy. He served during the Civil War as a coxswain on the USS John Adams.[nb 1] On November 28, 1864, he was involved in the capture of the blockade runner Beatrice off Sullivan's Island in Charleston Harbor. O'Brien commanded one of the launches which approached and boarded the ship despite heavy fire from the Confederate Fort Moultrie. Beatrice's equipment was then confiscated and the ship set afire. For these actions, O'Brien was awarded the Medal of Honor a month later on December 31, 1864.
O'Brien's official Medal of Honor citation reads:
Served as coxswain on board the U.S. Sloop John Adams, Sullivan's Island Channel, 28 November 1864. Taking part in the boarding of the blockade runner Beatrice while under heavy enemy fire from Fort Moultrie, O'Brien, who was in charge of one of the boarding launches, carried out his duties with prompt and energetic conduct. This action resulted in the firing of the Beatrice and the capture of a quantity of supplies from her.
- "Oliver O'Brien". Hall of Valor. Military Times. Retrieved February 3, 2013.
- "Civil War Medal of Honor Recipients (M–Z)". Medal of Honor Citations. United States Army Center of Military History. June 26, 2011. Retrieved February 3, 2013.
- Record of Medals of Honor issued to the officers and enlisted men of the United States Navy, Marine Corps, and Coast Guard. Washington: United States Government Printing Office. 1917. p. 86.
- Gaines, Nancy (July 3, 2011). "'Mustering' for the Civil War, 150 years ago". Gloucester Daily Times (Gloucester, Massachusetts). Archived from the original on October 9, 2012.