Short answers, pulled from the story.
The Second Battle of Fredericksburg took place on the 3rd of May 1863. Confederate forces under Major General Jubal A. Early defended positions near Fredericksburg against Union attacks led by Major General John Sedgwick.
Major General John Sedgwick commanded the Union forces including the VI Corps, I Corps, and part of the II Corps division during the battle. Brigadier General John Gibbon's division remained in Fredericksburg to guard the city after the fighting ended.
Confederate casualties totaled 700 men and four cannons during the engagement on the 3rd of May 1863. The photograph taken by Captain Andrew J. Russell shows the aftermath with bodies visible near the fortifications.
The outcome directly influenced General Robert E. Lee's ability to reinforce his main force at Chancellorsville by forcing him to divert troops from the primary battlefield. This diversion weakened Confederate strength where Joseph Hooker concentrated his four corps.
Soldiers from the 5th Wisconsin and 6th Maine Infantry regiments were among the first to mount the stone wall at Marye's Heights. Barksdale's brigade alongside Newton's division manned the center that Union forces targeted.