Maj. Gen. George B. McClellan advanced his lines with the objective of bringing Richmond within range of his siege guns.

Following the stalemate at the Battle of Seven Pines on May 31 and June 1, 1862, McClellan's Army of the Potomac sat passively in their positions around the eastern outskirts of Richmond.

Anticipating Jackson's reinforcements marching from the north, he increased cavalry patrols on likely avenues of approach.

Between the two armies was a small, dense forest, 1,200 yards (1,100 m) wide, bisected by the headwaters of White Oak Swamp.

Although Robinson and Grover made good progress on the left and in the center, Sickles's New Yorkers encountered difficulties moving through their abatis, then through the upper portions of the swamp, and finally met stiff Confederate resistance, all of which threw the Federal line out of alignment.

Gen. Robert Ransom's brigade, in their first combat engagement, delivered a perfectly synchronized volley of rifle fire against Sickles's brigade, breaking up its delayed attack and sending the 71st New York into a panicked retreat, which Sickles described as "disgraceful confusion.

At 1 p.m., seeing that the situation was not as bad as he had feared, McClellan ordered his men forward to retake the ground for which they had already fought once that day.

His attack gained only 600 yards (550 m) at a cost of over 1,000 casualties on both sides and was not strong enough to derail the offensive planned by Robert E. Lee, which already had been set in motion.