On August 9, 1862, the Union Second Corps under Major General Nathaniel Banks would clash with Confederate forces led by Major General Thomas J. "Stonewall" Jackson at Cedar Mountain. Federal forces initially gained the upper hand, but reinforcements led by Lt. General A.P. Hill allowed a flank attack the turned the tide of the battle and for the Confederates to win the day.
A total of 24,898 troops would face each that day—8,030 Union troops and 16,868 Confederate troops. It is estimated that there were 3,691 casualties.