CSS Atlanta, an 1006-ton ironclad ram, was originally built in Scotland in 1861 as the merchant steamship/blockade runner Fingal. In November 1861 she ran the blockade into Savannah, Georgia, with a large cargo of weapons and military supplies. After Union forces closed the exits from Savannah, preventing her further use as a blockade runner, Fingal was converted to an casemate ironclad and renamed Atlanta. She made her first appearance as a Confederate warship in mid-1862.
Atlanta made two efforts to attack Federal warships blockading the coast and rivers leading to Savannah. The first, in early 1863, was thwarted by obstructions blocking the route to the sea. In June 1863 Atlanta made her second attempt, targeting blockaders in Wassau Sound. There, on the 17th, she encountered the U.S. Navy monitors Nahant and Weehawken. In a brief battle, Atlanta went aground and was overwhelmed by Weehawken's superior firepower, forcing her to surrender.
The captured ironclad was taken into the Union Navy as USS Atlanta, commissioning for service in February 1864. She was stationed on the James River, Virginia, to support the operations of the army under General Ulysses S. Grant. On 21 May 1864, she fired on Confederate cavalry that were attacking Fort Powhatan. A year later, with the Civil War over, Atlanta went north and decommissioned at Philadelphia, Pennsylvania, in June 1865. After several years "in ordinary", she was sold in May 1869. Reportedly, she subsequently became the Haitian warship Triumph and disappeared at sea off Cape Hatteras in December 1869.