The triumph at Chancellorsville, however, came at great cost. The Confederates suffered 13,000 casualties, 22 percent of their force (the Union figures were 17,000 and 15 percent). The most grievous loss was Jackson, who had done so much to make the victory possible. And the boost that the battle gave to southern morale proved in the end harmful, for it bred an overconfidence in their own prowess and a contempt for the enemy that led to disaster. Believing his troops invincible, Lee was about to ask them to do the impossible.
