Phase One
Lt. Gen. Jackson marched with his 28,000 as planned, a trip that took nearly the entire day. To help mask this movement, Maj. Gen. James Ewell Brown (J.E.B.) Stuart ordered the 1st Virginia cavalry to march in advance of Jackson's column. The 2nd, 5th, and part of the 3rd regiments interposed between the Union left and Jackson's right flank.16

Hooker believed Stoneman had successfully cut Lee's supply line, so he stayed put, only ordering Maj. Gen. Daniel Sickles to attack with his 3rd Army Corps. Sickles broke through to the Catherine Furnace, a structure set up to assist the Confederacy in badly needed weapons manufacture. These forces ultimately gained control of the road upon which Jackson had already passed, although they were ultimately held by several smaller Confederate forces: Lieutenant Colonel (Lt. Col.) W. R. Carter, of the 3d Virginia Cavalry commanding the picket; Col. J. Thompson Brown assisting with two guns from his artillery; Captain (Capt.) W. S. Moore sending two companies of the 14th Tennessee Infantry; and finally General Archer moving his own brigade and that of Thomas back to also engage the enemy.

Sickles, caught in the fray, was left unaware of Jackson's march not long before. He managed at best to capture a few of the Confederate Second Corps men and gain a position of high ground, one of the few places artillery could be used effectively.

Phase Two
Although Maj. Gen. John Sedgwick remained at Frederickburg as ordered, telegraph lines between him and Maj. Gen. Joseph Hooker failed, making them unable to communicate with one another as planned. By the time an order arrived to Sedgwick to attack Maj. Gen. Jubal A. Early's single division, Sedgwick had decided the Confederate force was stronger than his own. Fearing that doing so would prove a mistake, Sedgwick remained where he was.

Phase Three
Gen. Hooker had ordered the commander of the rightmost Union flank (the 11th Corps), Maj. Gen. Oliver O. Howard, to prepare for a surprise attack by the Confederates. The 11,000-strong corps was composed heavily of German immigrants who were formerly under the command of Brig. Gen. Franz Sigel, who had requested relief in February of that same year. The corps developed low morale, being resentful of the general's decision and the appointment of the non-Germanic Howard. Many of them also had poor English and were subjected to ethnic friction with the rest of the Army of the Potomac. What was worse, however, of the 23 regiments making up the corps, 8 lacked any experience in battle, and the rest had never been on the winning side of combat.

In spite of his orders, Howard failed to prepare his corps to defend itself adequately. At 5:30 p.m., while many of Howard's corps were cooking dinner, Lt. Gen. Jackson commanded his 26,000 men to attack. Over 4,000 of the 11th Corps surrendered without a single shot; all but one division of the rest were routed nearly immediately; and the division that remained did not hold its ground for very long. By nightfall, the Confederate 2nd Corps had reached sight of Chancellorsville, where a small Union force was all that stood between them and Lee's army: Maj. Gen. Sickles hadn't moved since that morning.

Not long after, however, Maj. Gen. Hooker ordered the return of Sickles' 3rd Corps to Chancellorsville because his position was a salient. This aided the Confederates by reuniting Jackson with Gen. Lee. Unfortunately, this also gave them Hazel Grove, one of the few places where artillery could be effective. Sickles was quite bitter about giving up this high ground, but he obeyed and retreated from the area.

Confederate Tragedy
Jackson had won a major victory over the Union forces that day. Realizing the disparity of army strength between Hooker's forces and Lee's, he decided to forward his advantage before a counterattack could be mounted. While scouting the Orange Plank Road that night, his own men of the 2nd Corps mistakenly shot him. The wound itself was not mortal, but he died from complications only days after being shot.

Battle of Chancellorsville