Prior to the Civil War, Mullany served at sea in almost every part of the globe.
From January until March, 1861, he served on the frigate USS Sabine in the protection of Fort Pickens in Pensacola, Florida. In April and May of that year, he was in command of the gunboat USS Wyandotte and occupied a position in Pensacola in the rear of Fort Pickens, which was at the time under serious threat of attack. He also assisted in re-enforcing the fort on April 12, 1861.
He was commissioned commander, 18 October 1861, and assigned to the USS Bienville in the North Atlantic and West Gulf Squadrons where he remained until April 1862 until May 1865. Much of that
When Farragut proposed to attack Mobile Bay, Mullany volunteered his services, but Farragut did not consider the Bienville as fit to engage the forts, he was given the command of the steamer USS Oneida. time, he was under threat of enemy fire.
The Oneida was lashed to the former ironclad USS Galena on the side toward Fort Morgan and at the end of the line of ships passing that fort on 5 August 1864. As such, it was exposed to a very destructive fire from the fort,
Later, the Oneida engaged the Confederate ram CSS Tennessee which was able to rake the wooden ship with its cannons, causing even more damage.
--Old B-Runner