Saugus was assigned to the James River Flotilla and arrived at
Fort Monroe on 1 May. By 22 May, the ship was deployed with her sisters and
Tecumseh on the James River where they protected the transports of
Major General Benjamin Butler's
Army of the James, supplying the army as it operated on the south bank of the river during the
Bermuda Hundred Campaign. On 21 June, Commander Craven of the
Tecumseh spotted a line of
breastworks that the Confederates were building at Howlett's Farm and his ship opened fire at the workers. The Confederates replied with a battery of four guns near the breastworks and
Saugus and
Canonicus joined in the bombardment. A half-hour later, Confederate ships near
Dutch Gap joined in, but their fire was ineffective because they were firing blindly at the Union monitors. During the engagement,
Saugus fired thirty-six 15-inch shells and was hit once by a Confederate shell that struck the deck and ricocheted into the turret; no one was wounded or killed during the engagement. Eight days later,
Saugus and the side-wheel
gunboat engaged a battery at Deep Bottom Creek. The same pair of ships engaged another battery on Four Mile Creek on 30 June and 1 July.
Saugus was still under repair at the
Norfolk Navy Yard in early September when she received orders to proceed with
Canonicus and the gunboats and to
Port Royal, South Carolina, and there await Admiral
David Farragut, the prospective commander of the North Atlantic Blockading Squadron, in anticipation of an attack on Fort Fisher. This deployment was cancelled on 19 September when poor health caused Farragut to decline the appointment. The ship returned to the James and resumed supporting the
Union Army. In an engagement with Howlett's Battery on 5 December,
Saugus was hit twice. One of the shots from a
Brooke rifle disabled her turret temporarily when it cracked an armor plate and broke a number of bolts. The monitor ran aground on 14 December and she was refloated the following day.
Saugus was repaired at Norfolk and she was then towed by the gunboat
Nereus. They departed on 22 December and arrived off Fort Fisher on
Christmas Eve. Towed by the side-wheel gunboat ,
Saugus arrived back at Fort Fisher on 13 January 1865. Together with her sisters
Canonicus and , the double-turreted monitor and the
armored frigate , she bombarded the fort for three days until it was captured by Union troops. Despite the bursting of one of her guns on 13 January, which wounded one crewman, the ship fired 212 shells during the battle.
Saugus was hit 11 times, cracking armor plates on her pilothouse and turret in addition to breaking bolts, but she was not badly damaged. Nonetheless, the monitor was ordered to return to Norfolk for repairs on 16 January, towed by the sidewheel gunboat . On 23 January, as the ship was en route for the
Washington Navy Yard for repairs, the Confederate
James River Squadron attempted to
slip through the obstructions at Trent's Reach for an attack on the Union gunboats and transports, but they were repulsed before
Saugus reached
City Point four days later. After the assassination of President
Abraham Lincoln on 15 April, eight of the suspected conspirators were incarcerated aboard
Saugus and the monitor . On 30 April, they were transferred off the ships to the
Arsenal Penitentiary. == Post-war operations ==