The Confederate army under Lee and the…

The Confederate army under Lee and the Union force under Hooker, following the “horror of Fredericksburg”, have spent the winter facing each other across the Rappahannock River in Virginia.

Hooker, having effected several much-needed organizational reforms in the Army of the Potomac and prepares to challenge the Confederate forces.

Taking the offensive on April 27, Hooker dispatches his cavalry behind Lee's army, intending to cut off a retreat.

Two days later, he sends a small diversionary force across the Rappahannock below Fredericksburg and crosses upriver with the main body of his army.

By May 1, his superior forces are massed near Chancellorsville, a crossroads in a densely forested lowland called the Wilderness.

Deprived of his cavalry, however, Hooker is blind to Lee's movements, and on May 2, when Lee orders Stonewall Jackson's “foot cavalry” to swing around and attack the Union right, Hooker's surprised flank is routed.

Outmaneuvered, Hooker withdraws, and Lee's pressure over the next three days forces a Union retreat north of the river.

Although the Union's soldiers outnumbered the Confederates more than 2 to 1 (133,868 Union, 60,892 Confederate), Hooker's Army has lost 17,278 troops.

The Confederate forces lose 12,821 soldiers, but the South's greatest casualty is that of Jackson, who dies on May 10 of battle wounds.