Hooker arrived late in the afternoon on April 30 and made the mansion his headquarters. Stoneman's cavalry began on April 30 its second attempt to reach Lee's rear areas. Two divisions of II Corps crossed at U.S. Ford on April 30 without opposition.

Meade’s Fifth Corps reached the Chancellorsville clearing. Richard Anderson’s Confederate Division dug in at Zoan Church. Most of Jackson’s Corps began its march from the Fredericksburg area. Early’s Division and Barksdale’s Brigade from McLaws’ Division were left behind to cover the Fredericksburg crossings, 10,000 men to defend against 60,000.

Pleased with the success of the operation so far, and realizing that the Confederates were not vigorously opposing the river crossings, Hooker ordered Sickles to begin the movement of the III Corps from Falmouth the night of April 30 – May 1. By May 1, Hooker had approximately 70,000 men concentrated in and around Chancellorsville.^[1]

In his Fredericksburg headquarters, Lee was initially in the dark about the Union intentions and he suspected that the main column under Slocum was heading towards Gordonsville. Jeb Stuart's cavalry was cut off at first by Stoneman's departure on April 30, but they were soon able to move freely around the army's flanks on their reconnaissance missions after almost all their Union counterparts had left the area.^[2]

As Stuart's intelligence information about the Union river crossings began to arrive, Lee did not react as Hooker had anticipated. He decided to violate one of the generally accepted principles of war and divide his force in the face of a superior enemy, hoping that aggressive action would allow him to attack and defeat a portion of Hooker's army before it could be fully concentrated against him. He became convinced that Sedgwick's force would demonstrate against him, but not become a serious threat, so he ordered about 4/5 of his army to meet the challenge from Chancellorsville. He left behind a brigade under Brig. Gen. William Barksdale on heavily fortified Marye's Heights behind Fredericksburg and one division under Maj. Gen. Jubal A. Early, on Prospect Hill south of the town.^[2]

These roughly 11,000 men and 56 guns would attempt to resist any advance by Sedgwick's 40,000. He ordered Stonewall Jackson to march west and link up with Maj. Gen. Richard H. Anderson's division, which had pulled back from the river crossings they were guarding and began digging earthworks on a north-south line between the Zoan and Tabernacle churches. McLaws's division was ordered from Fredericksburg to join Anderson. This would amass 40,000 men to confront Hooker's movement east from Chancellorsville. Heavy fog along the Rappahannock masked some of these westward movements and Sedgwick chose to wait until he could determine the enemy's intentions.^[2]