William Martin (born 1839, date of death unknown) 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 at the Battle of Forts Jackson and St. Philip.
Born in 1839 in Ireland, Martin immigrated to the United States and was living in New York when he joined the U.S. Navy. He served during the Civil War as a seaman on the USS Varuna. At the Battle of Forts Jackson and St. Philip near New Orleans on April 24, 1862, Varuna was rammed twice by the Confederate steamer CSS Governor Moore (formerly known as the Charles Morgan) and eventually sunk. Martin acted as a gun captain and was "cool and courageous" throughout the close-range fight. For this action, he was awarded the Medal of Honor a year later, on April 3, 1863.
Martin's official Medal of Honor citation reads:
Captain of a gun on board the U.S.S. Varuna during an attack on Forts Jackson and St. Philip, 24 April 1862. His ship was taken under furious fire by the rebel Morgan and severely damaged by ramming. Steadfast at his station through the thickest of the fight, Martin inflicted damage on the enemy, remaining cool and courageous although the Varuna, so badly damaged that she was forced to beach, was finally sunk.