John Rannahan was born about 1835 - 1836 in Monaghan County, Ireland. He immigrated to the United States.
Rannahan volunteered in 1861 to serve as a United States Marine. His enlistment was credited to Pennsylvania, and he was assigned to the USS Minnesota. On January 15th 1865 he was part of a landing party that was to storm the Confederate held Fort Fisher on the coast of North Carolina. The storming party was made up of marines, sailors and soldiers under the joint command of Union Admiral David Dixon Porter and General Alfred Terry.
Rannahan was awarded the Medal of Honor on June 22nd 1865. The citation reads, “The President of the United States of America, in the name of Congress, takes pleasure in presenting the Medal of Honor to Corporal John Rannahan, United States Marine Corps, for extraordinary heroism in action on board the U.S.S. Minnesota in the assault on Fort Fisher, 15 January 1865. Landing on the beach with the assaulting party from his ship, Corporal Rannahan advanced to the top of the sand hill and partly through the breach in the palisades despite enemy fire which killed or wounded many officers and men. When more than two-thirds of the men became seized with panic and retreated on the run, he remained with the party until dark when it came safely away, bringing its wounded, its arms and its colors.”
Rannahan died June 1st 1892 in Millwood, Westmoreland, Pennsylvania. He is buried in the Saint Martins Cemetery in New Derry, Pennsylvania.