Maj. Gen. Joseph Hooker launched his spring campaign in late April 1863. With a 2 to 1 numerical advantage over Robert E. Lee and the Army of Northern Virginia, Hooker marched the bulk of his Army of the Potomac around the Confederate left. By the evening of April 30, Hooker arrived at Chancellorsville, twelve miles in Lee's rear at Fredericksburg. The next day he sent columns toward the Confederates. Lee responded by dividing his army and moving to meet Hooker. The two sides collided on May 1.
Although the Southerners stalled Hooker’s army in the Wilderness on May 1, Lee and Jackson knew that they needed to retain the initiative. Lee devised an audacious plan for Jackson to attack the Federals’ vulnerable western flank, which was not anchored by defensible terrain. Jackson concurred, and left camp at 8 am on May 2 with two-thirds of the Rebel forces on a roundabout clandestine march.
On the morning and early afternoon of May 2, Gen. Stonewall Jackson's huge flanking column marched stealthily along brush-choked paths. The general deceived Union observers by turning south before quickly veering north on a little-known wagon trail. Shortly after crossing Poplar Run, Jackson made the impromptu decision to redirect his march again, which ultimately enabled him to reach the extreme western flank of Joseph Hooker’s unprepared Union army.
Jackson's Flank Attack
Joseph Hooker's right flank, Maj. Gen. Oliver O. Howard's XI Corps stretched west from the area around Chancellorsville along the Orange Turnpike. Howard's line was not anchored on any geographical feature or "in the air" and offered an inviting target for Lee and Jackson. On the evening of May 2, Jackson struck and within two hours completely stampeded Howard's corps from the field.
As panicked troops from Gen. Oliver O. Howard’s Eleventh Corps fled from Stonewall Jackson’s crushing surprise attack, Union officers hurriedly organized defenses at the “Buschbeck Line.” Although Jackson drove back Howard’s last line of defense, disorganization and darkness stalled the attack around sunset. Seeking to press his advantage, Jackson rode ahead of his troops to reconnoiter for a potential night attack but was mortally wounded by friendly fire.
After routing the Union Eleventh Corps, Robert E. Lee was desperate to reunite his force with that of Stonewall Jackson at the Chancellorsville crossroads. Renowned cavalry Gen. J.E.B. Stuart took the place of the wounded Gen. Jackson on May 3. Stuart and Lee closed in on Chancellorsville from three directions – capturing key high ground at Hazel Grove and pummeling the vulnerable Union defenses.
By mid-morning on May 3, Confederate forces had reunited and were drawing a cordon of grey around the Union defenders at Chancellorsville. After a near-miss by a Southern cannonball knocked him off his feet, a disoriented and rattled Gen. Hooker determined to pull his Federals back from the Chancellorsville crossroads and wait for the arrival of reinforcements advancing from Fredericksburg.
Ordered to Hooker's aid from the Maj. Gen. John Sedgwick's VI Corps broke through the Confederate position at Fredericksburg on May 3 and pushed west. Lee rushed Lafayette McLaws's division to meet Sedgwick. McLaws took up a position along a ridge dotted by Salem Church. Sedgwick launched an assault but was driven back by the Confederates. Sedgwick held out against attacks on May 4 and finally withdrew the next day. Hooker began his retreat from Chancellorsville that night ending the campaign.