Prelude to the Battle
On March 17, 1862, Union General George B. McClellan launched his Peninsula Campaign. McClellan planned to transport the Army of the Potomac by ship to Fort Monroe, on the peninsula between the York and James Rivers in southeastern Virginia. With the bulk of the Confederate forces positioned in northern Virginia, near Manassas Junction, McClellan planned to advance up the peninsula and capture Richmond, the Confederate capital, and bring the American Civil War to a quick end.
McClellan’s Delay Buys Johnston Time
On April 4, McClellan’s 120,000-man army began its march up the peninsula. The next day, the advance came to a halt when the Federals encountered Confederate forces of about 10,000 men, dug in along the Warwick River near Yorktown. Erroneously believing that the Rebel forces outnumbered his army, McClellan settled in for a siege rather than attack. The resulting one-month delay enabled Confederate General Joseph E. Johnston to redeploy troops from northern Virginia to the peninsula. Despite the delay at Yorktown, by late May, McClellan’s army had his army encamped along both sides of the Chickahominy River, only several miles from Richmond.
May 31–June 1, 1862 — Clash Near Seven Pines, Virginia
When heavy spring rains flooded the Chickahominy, Johnston seized the opportunity to attack McClellan’s army while the swollen river divided it. On May 31, Confederate troops launched attacks against the isolated 3rd and 4th Corps of the Army of the Potomac near Seven Pines and Fair Oaks, Virginia. The Rebels made some initial headway, but the Federals held when reinforcements arrived late in the day.
Around dusk, General Johnston was severely wounded, and G.W. Smith assumed temporary command of the army. Smith renewed the attack on June 1, but the Confederates made little headway against the reinforced Federals. The battle ended on the evening of June 1.
Aftermath of the Battle
The Battle of Seven Pines was inconclusive tactically. Both sides claimed victory, but neither side had achieved much.
Strategically, the battle was much more important. Confederate President Jefferson Davis used Johnston’s injury as an opportunity to place the more aggressive General Robert E. Lee in command of the Army of Northern Virginia.
After the battle, McClellan redeployed most of his army south of the Chickahominy and continued to plan for a siege of Richmond. Taking advantage of McClellan’s inactivity, on June 25, Lee launched the first of six assaults on federal troops in seven days, collectively known as the Seven Days Battles (June 25 to July 1, 1862). The Seven Days Battles drove the Army of the Potomac away from Richmond and back down the peninsula.
In May, the Army of the Potomac had been within sight of the Confederate capital. By July, with McClellan’s army in retreat, Lee could turn his attention to the Union’s Army of Virginia, less than thirty miles from Washington, and inflict another disastrous federal defeat at Manassas Junction, opening the way for a Confederate invasion of the North.