Of all the Civil War battles fought, and of all the victories achieved by Robert E. Lee at the command of the Confederate Army of Northern Virginia, the Battle of Chancellorsville is considered the most tactically complex and ultimately the most brilliant Confederate victory of the war.

In early May 1863, the Army of the Potomac was at the height of its power as it bore down on Robert E. Lee's Army of Northern Virginia near Fredericksburg, where the Confederates had defeated them the previous December. The Union behemoth had spent most of the winter season being reorganized and drilled by "Fighting Joe" Hooker, an aggressive commander who had fought hard at places like Antietam. With an army nearing 130,000 men, Hooker's Army of the Potomac was twice the size of the Army of Northern Virginia.

With that advantage, Hooker proposed a daring and aggressive two pronged attack that aimed to keep Lee's army occupied in front of Fredericksburg, while marching around its left. Meanwhile, a cavalry raid well in the rear was intended to cut Lee's lines of supplies and possible retreat. Hooker's plan initially worked perfectly, with the division of his army surprising Lee. At the end of May 1, Lee was outnumbered two-to-one and now had to worry about threats on two fronts.