(Mon: t. 1,250; l. 226'; b. 49'3"; dph. 13'2"; dr. 12'0"; s. 9 k.; cpl. 150; a. 2 15" D.sb., 2 150-pdr. P.r.; cl. Onondaga)
A lake and county in New York.
The first Onondaga, a double turreted monitor, was launched 2 July 1864 by Continental Iron Works, Greenpoint, N. Y., under subcontract from George W. Quintard; sponsored by Miss Sally Sedgwick, daughter of former U. S. Representative Charles Baldwin Sedgwick, who codified naval laws for the Navy Department; and commissioned at New York Navy Yard 24 March 1864, Capt. Melancthon Smith in command.
With Mattabesset, the new monitor departed New York 21 April 1864, and arrived Hampton Roads two days later. Operating primarily in the James River Flotilla, Onondaga supported General Grant's drive on Richmond. On 24 November with Mahopac she engaged Southern batteries on the James at Howlett's, Va., and resumed the attack 5 and 6 December.
Early in January much of the Union strength was withdrawn from the James as Admiral Porter assembled his powerful fleet for the forthcoming attack on Fort Fisher, N. C., which protected Wilmington. Onondaga was the only monitor left to guard Union forces on and along the James against Flag Officer John K. Mitchell's Confederate James River Squadron. When the Southern force steamed down river to attack the weakened Union forces there afloat, the monitor dropped downstream to a position affording her greater maneuverability. She and her supporting gunboats awaited the Southern attack only to have the Confederate thrust blunted when Mitchell's ironclads Virginia No. 2 and Richmond, gunboat Drewry, and torpedo boat Scorpion all ran aground trying to pass obstructions at Trent's Reach. After attacks by Northern shore batteries and Onondaga, Drewry exploded, Scorpion was abandoned, and the two Southern ironclads withdrew upriver when they were refloated the next day.
After continuing to support Union troops fighting to take the Confederate capital until General Lee was forced to abandon Richmond, Onondaga steamed north and decommissioned at New York 8 June 1865 and was laid up at League Island, Pa. By Act of Congress approved 7 March 1867, the monitor was sold to her builder, G. W. Quintard and subsequently resold to France for service in the French Navy under the same name.