CSS[Note 1] Fredericksburg was a casemate ironclad that served as part of the James River Squadron of the Confederate States Navy during the American Civil War.

After passing through the obstructions at Drewry's Bluff in May 1864, she participated in several minor actions on the James River and fought in the Battle of Chaffin's Farm from September 29 to October 1.

In mid-1862, Fredericksburg was laid down by the Confederate States Navy in the Rocketts Landing area of Richmond, Virginia to a plan by the Chief Naval Constructor, John L. Porter.

By substituting straight lines and angles for the traditional keel and curving frame of the hull, Porter optimized his design to be quickly built by ordinary carpenters, rather than highly skilled shipwrights that were in short supply in the Confederacy, at the cost of being able to mount fewer guns than those ironclads built with traditional hulls.

[2] Porter supervised the work of constructing Fredericksburg,[3] but it is uncertain how exactly he followed his design as surviving documents disagree in many ways.

[6] High waters on the James River in early 1864 threatened to wash away stockpiles of timber and inundate the shipyard's wharves, further delaying her completion.

General P. G. T. Beauregard placed artillery batteries along the south side of the river to support the naval advance, but Fredericksburg suffered boiler damage on May 29 that required a day to repair.

[29] Union forces under the command of Major General Benjamin Butler began building the Dutch Gap Canal in August to try to bypass Confederate land defenses in the area.

[33][32] On September 29, Butler's Union Army of the James attacked the Confederate land positions in the Battle of Chaffin's Farm.

[36] The three ironclads moved against the battery to allow the wooden gunboats of the fleet to escape, before falling back to Chaffin's Bluff.

[38] On October 24, Fredericksburg was sent upriver to the Rocketts area, where she was given a replacement cannon for the gun that had burst and had the roof of her casemate protected with iron bars.

[39] Fredericksburg, Virginia II, and Richmond went down to Fort Brady on December 7 and exchanged fire with the Union position.

[40] By the beginning of 1865, the situation was becoming bleaker for the Confederates due to several military defeats, and it was decided to risk an attack against the Union fleet on the James in hopes of breaking the blockade on the river and destroying the depot at City Point.

[44] Virginia II ran aground, and the Confederates decided not to push further that night and recalled Fredericksburg and Hampton back across the obstructions.

[46] Union vessels arrived during the morning and reached the obstructions, firing on the now-freed Virginia II, and Richmond who were still in the process of moving upriver towards the battery.

The two Confederate ironclads were able to reach the safety of Battery Dantzler, which provided fire support, striking the gunboat USS Massasoit.

While the Confederates considered another attempt through the obstructions that night, it was decided not to risk a movement, and the surviving vessels of Mitchell's squadron withdrew to Chaffin's Bluff.

[48] Shortly after the battle at Trent's Reach, Mitchell was replaced as commander of the James River Squadron by Admiral Raphael Semmes.

[49] The men of the James River Squadron served on land, moving with the Confederate government to Danville, Virginia, before eventually surrendering in North Carolina.