By late afternoon on 17 Apr. 1864, three brigades of infantry-about 10,000 troops-commanded by Hoke was within five miles of Plymouth. Defending the town was a Union garrison of 2,834 men. Although badly outnumbered, the Federals had strongly fortified the post and repulsed the first Confederate attacks. But the next day, 18 April, saw heavy shelling, with Union vessels in the river sunk or damaged and forced to retreat to Plymouth. Meanwhile, U.S. Navy gunboats provided artillery support against the Confederates, but their success was short-lived.
During the night the Albemarle, taking advantage of an abnormally high river level, safely passed over the obstructions and slipped undamaged past Fort Gray, west of Plymouth. In the predawn hours of 19 April, Cooke's ship encountered the USS Southfield and USS Miami, the most powerful Union vessels on the Roanoke. The Albemarle promptly sank the first and heavily damaged the second, forcing the Miami and two other gunboats to retreat. Late that afternoon, Hoke launched a double envelopment attack against both the east and west sides of the town. The Albemarle, having returned to Plymouth, furnished supporting fire on the east side of town.
On 20 April Hoke renewed the attack on each flank, capturing forts from both directions. But the Union commander, Brig. Gen. Henry Wessels, refused to surrender and gathered the remainder of his forces inside Fort Williams, the Federals' last remaining stronghold, near the center of Plymouth. Hoke unleashed his artillery on the bastion, and the Albemarle added its two large rifled cannons to the bombardment. Heavily shelled from all sides, Wessels unconditionally surrendered his entire command. In addition to the Union garrison, Hoke captured 25 artillery pieces, at a cost of only 50 Confederates killed and wounded. His victory provided a badly needed morale boost for the Confederacy.
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