The Second Battle of Fredericksburg, also known as the Second Battle of Marye's Heights, took place on May 3, 1863, in Fredericksburg, Virginia, as part of the Chancellorsville Campaign of the American Civil War.
Confederate Gen. Robert E. Lee left Maj. Gen. Jubal A. Early to hold Fredericksburg on May 1, while he marched west with the rest of the Army of Northern Virginia to deal with Union Maj. Gen. Joseph Hooker's main thrust at Chancellorsville with four corps of the Army of the Potomac. Early had his own division, along with William Barksdale's brigade from McLaws' division and cannons from the artillery reserve; Early was assisted by Brigadier General William Pendleton of the artillery reserve. Cadmus Wilcox's brigade arrived on May 3, increasing Early's strength to 12,000 men and 45 cannons. Most of the Confederate force was deployed south of Fredericksburg.
Early was ordered by Lee to watch the remaining Union force near Fredericksburg; if he was attacked and defeated, he was to retreat southward to protect the Confederate supply lines. If the Union force moved to reinforce Hooker, then Early was to leave a covering force and rejoin Lee with the remainder of his troops.  On May 2, misunderstanding his orders, Early left one brigade at Fredericksburg and started the rest of his force towards Chancellorsville; Lee corrected the misunderstanding and Early then returned to his positions that night before Sedgwick discovered the Confederate retreat. 
Maj. Gen. John Sedgwick was left near Fredericksburg with the VI Corps, the I Corps, and the II Corps division of Brig. Gen. John Gibbon. Hooker's plan called for Sedgwick to demonstrate near the city in order to deceive Lee about the Union plan. The VI and II Corps seized control of several crossings on April 29, laying down pontoon bridges in the early morning hours, and the divisions of W.H.T. Brooks and James S. Wadsworth crossed the river. The I Corps was ordered to reinforce the main army at Chancellorsville during the night of May 1. During the evening of May 2, Sedgwick received orders to attack Early with his remaining forces. 
Sedgwick moved his forces into Fredericksburg during dawn on May 3, uniting with Gibbon's division which had crossed the river just before dawn. Sedgwick originally planned to attack the ends of Marye's Heights but a canal and a stream blocked the Union forces. He then decided to launch an attack on the Confederate center on the heights, which was manned by Barksdale's brigade, with John Newton's division; this attack was defeated. Colonel Thomas M. Griffin of the 18th Mississippi Infantry granted the Union forces a truce in order to gather in their wounded. During this truce, the Union commanders noticed that the flank of Barksdale's left regiment was unprotected. 
Sedgwick launched another attack against this flank and Barksdale's front using elements from all three VI Corps divisions, which pushed the Confederate forces off the ridge, capturing some artillery. The first men to mount the stone wall were from the 5th Wisconsin and the 6th Maine Infantry regiments. Barksdale retreated to Lee's Hill, where he attempted to make another stand but was again forced to retreat southward. 
Confederate casualties totaled 700 men and four cannons. Early withdrew with his division two miles to the south, while Wilcox withdrew westward, slowing Sedgwick's advance. When he learned of the Confederate defeat, Lee started moving two divisions east to stop Sedgwick.  Following the campaign, Early became embroiled in an argument with Barksdale over what Barksdale considered a slight to his brigade in a newspaper letter that Early had written; the exchange continued until Lee ordered the two generals to cease. 
Sedgwick had lost 1,100 men during the engagement. At first he started to pursue Early's division but then followed the orders he received the previous day and started west along the Plank Road towards Hooker's army at Chancellorsville. Gibbon's division was left in Fredericksburg to guard the city. 
- Sears, p. 309.
- Furgurson, p. 261.
- Sears, p. 357.
- Davis, p. 37.
- Gallagher, p. 40–41; Furgurson, pp. 257–61.
- Davis, p. 32.
- Sears, pp. 140–41, 169, 283–84, 309; Furgurson, pp. 97–100, 147.
- Furgurson, pp. 256–58, 261–63.
- Furgurson, pp. 263–67; Davis, pp. 36–37.
- Davis, p. 37; Sears, pp. 373–75; Furgurson, pp. 268–69.
- Gallagher, pp. 54–58.
- Sears, pp. 375–76; Furgurson, p. 267.
- Davis, Danny. "Return to Fredericksburg." America's Civil War 5, no. 4 (September 1992): 30–37.
- Catton, Bruce. Glory Road. Garden City, New York: Doubleday and Company, 1952. ISBN 0-385-04167-5.
- Furgurson, Ernest B. Chancellorsville 1863: The Souls of the Brave. New York: Knopf, 1992. ISBN 0-394-58301-9.
- Gallagher, Gary W. "East of Chancellorsville: Jubal A. Early at Second Fredericksburg and Salem Church" in Chancellorsville: The Battle and Its Aftermath, edited by Gary W. Gallagher. Chapel Hill: University of North Carolina Press, 1996. ISBN 0-8078-2275-2.
- Sears, Stephen W. Chancellorsville. Boston: Houghton Mifflin, 1996. ISBN 0-395-87744-X.
- Parsons, Philip W. "The union Sixth Army Corps in the Chancellorsville Campaign: A Study of the Engagements of Second Fredericksburg, Salem Church, and Banks's Ford, May 3–4, 1863" McFarland and Company, Inc. Jefferson, North Carolina and London. 2006. ISBN 0-7864-2521-0.
- Mackowski, Chris, and Kristopher D. White. Chancellorsville's Forgotten Front: The Battles of Second Fredericksburg and Salem Church, May 3, 1863. El Dorado Hills, CA: Savas Beatie, 2013. ISBN 978-1-61121-136-8.
- NPS battle description
- National Park Service Battle Summary
- CWSAC Report Update
- NPS Fredericksburg & Spotsylvania County Battlefield site
- Second Battle of Fredericksburg in Encyclopedia Virginia