Maj. Gen. Joseph Hooker’s well-executed crossing of the Rappahannock fords on April 30, 1863 placed his rejuvenated and reorganized Army of the Potomac on Lee’s vulnerable flank. Rather than retreat before this sizable Federal force, Lee opted to attack Hooker while he was still within the thick wilderness. Late on May 1, 1863, Lee and Jackson conceived one of the boldest plans of the war. Jackson, with 30,000 Confederates, would follow a circuitous route to the Union right and from there conduct an attack on that exposed flank. The May 2, 1863 flank attack stunned the Union XI corps and threatened Hooker’s position, but the victorious Confederate attack ended with the mortal wounding of Stonewall Jackson. On May 3, 1863, the Confederates resumed their offensive and drove Hooker’s larger army back to a new defensive line nearer the fords. Swinging east, Lee then defeated a separate Federal force near Salem Church that had threatened his rear. Lee's victory at Chancellorsville is widely considered to be his greatest of the entire war.