Fort McAllister I

Fort McAllister in Bryan County, Georgia became the site of a string of naval assaults spanning January 27 to March 3, 1863, during the American Civil War, an episode later remembered as the First Battle of Fort McAllister. Rear Adm. Samuel F. Du Pont, who led the South Atlantic Blockading Squadron, wanted to see how his new monitors performed against the fort before committing to a larger campaign aimed at Charleston, South Carolina.

Earlier operations

F

Initial attacks

Admiral Du Pont sent an ironclad vessel upriver with three goals: seize the fort, destroy the Nashville, and set fire to the Atlantic and Gulf railway bridge situated farther along the waterway. The mission also served as the debut trial for the newly built Passaic class of ironclad monitor, a warship fitted with an enormous 15 inch Dahlgren gun, the heaviest naval cannon of that era. Its single turret held not just this massive weapon but an 11 inch Dahlgren as well.

The fort came under renewed assault on January 27, 1863, when the monitor USS Montauk arrived alongside three gunboats and a mortar schooner. Commander John L. Worden directed the Montauk's guns against the fortification for five straight hours, firing from a distance of between 1,500 and 1,800 yards. Though the shelling tore through and gouged the parapets, it left no permanent damage and produced no casualties among the defenders. The fort's gunners managed thirteen strikes of their own, yet accomplished little more than denting the ship's armor plating and sinking a small launch. Overnight, the garrison quietly rebuilt what the bombardment had broken.

Worden returned on February 1 for another attempt at silencing the position. Scouts working for the Union had crept out the previous night and cleared several mines from the channel, clearing a path for the ships to close the distance. This time the Montauk pressed to within just 600 yards and kept up fire for another five hours. The assault proved fatal for the fort's commanding officer, Major John B. Gallie, and left seven others wounded. Command then passed to Major George Wayne Anderson in the wake of Gallie's death. The Montauk did not escape unscathed either, absorbing 48 hits that temporarily jammed its turret. In the aftermath, defenders reinforced the river's defenses further by laying nine Rains torpedoes in the very stretch of channel where the Montauk had pressed its attack.

Destruction of the Nashville/Rattlesnake

Having failed to slip past the Federal blockade, the Nashville underwent conversion into an armed raider for commerce warfare, placed under the command of Capt. Thomas H. Baker, and received a new name: the Rattlesnake. On February 27, amid rainy conditions, Baker tried to reach open water but was blocked by a Union vessel patrolling the area. Forced back, the raider grounded itself on a river bend some distance upstream from the fort, though it remained within sight of the blockading ships.

The following morning, Worden positioned the Montauk roughly 1,200 yards from the fort, placing it at nearly the same distance from the stranded Rattlesnake. The monitor opened fire on the grounded ship while the fort's guns targeted the ironclad in hopes of pulling its attention away. Within minutes, the Montauk's fifth round struck home in the raider's hull. That hit, along with the shells that followed, sparked flames and eventually a series of explosions that finished off the vessel entirely. In total, the Montauk had expended fourteen rounds during the engagement.

As it made its way back down the river afterward, the Montauk struck a mine. The crew's commander and pilot responded swiftly, guiding the damaged ironclad onto a mud bank as the tide fell, which kept the breach sealed long enough for makeshift repairs. Once patched, the vessel floated free again when the tide rose. It was later sent to Port Royal, where lasting repairs could finally be made.

Aftermath and conclusions

When the massive 15-inch Dahlgren gun and the single-turret monitors first faced the sand parapets of Fort McAllister, the engagement exposed a number of weaknesses and lessons.

Because the huge cannon fired so slowly from their two-gun turrets, they lacked real offensive punch, and this gave the fort's defenders time to shoot at the exposed gun ports before ducking back under cover. The garrison could return fire at a much faster pace than the ships could manage. Even with multiple monitors firing together, the combined volume never reached a level capable of silencing the battery.

The vessels also proved prone to mechanical trouble, including turret rings that jammed and other gun failures that could knock a battery out of the fight entirely. Although the armor plating stopped shells from penetrating, the crews still faced danger from bolts that shattered and sent fragments flying on impact. The decks of the monitors, being thin, were exposed to the danger of mortar shells dropping down onto them.

Damage to earthworks could be fixed quickly, often within a single night or by the next day, letting a garrison return to full strength almost as if nothing had happened. Firing mortars at a fort from long range turned out to be too imprecise to accomplish much. To keep a fort from mending its defenses, continuous suppressing fire through the night would be necessary. Passing a fort remained dangerous even for ships that could withstand its guns, since mines and obstructions blocked the way regardless of the monitors' resistance to shellfire. Forts built of sand withstood bombardment far better than those made of mud. Forts equipped with well built traverses and bombproofs also resisted being disabled through flanking fire.

As he readied his forces for the assault on Charleston, Du Pont worked to correct these problems however he could. He directed that additional armor be added to reinforce the decks, and he tried to devise a "submarine torpedo exploder" mounted on the bows of his ships to clear away mines. To boost the total firepower brought against the enemy's defenses, he committed as many ironclads to the operation as possible.

Despite these efforts, the concerns Du Pont raised about the monitors' inability to overcome earthen fortifications were largely ignored as the Charleston harbor operation moved forward. That assault ended in failure, costing the Union the ironclad USS Keokuk, which was lost during the attempt. Du Pont ultimately resigned, taking responsibility for the defeat at Charleston.

As for Fort McAllister itself, no naval bombardment ever forced its surrender. Its fall finally came through an infantry assault at the close of Sherman's March to the Sea in December 1864.