May 31 – June 1, 1862
The Battle of Seven Pines, also known as the Battle of Fair Oaks, took place near Seven Pines and Fair Oaks, Virginia, on May 31 and June 1, 1862. The battle was an important turning point in Union General George B. McClellan's Peninsula Campaign.
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.
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 his army was outnumbered, McClellan settled in for a siege, rather than attack. The resulting one-month delay enabled Confederate General Joseph Johnston to redeploy troops from northern Virginia to the peninsula. Despite the delay at Yorktown, by late May, McClellan's army was encamped along both sides of the Chickahominy River, only several miles from Richmond.
When heavy spring rains flooded the Chickahominy, Johnston seized the opportunity to attack McClellan's army while it was separated by the swollen river. On May 31, Confederate troops launched attacks against the isolated Third and Fourth of Corps of the Army of the Potomac near Seven Pines and Fair Oaks, Virginia. The attacks were poorly executed, and although the Rebels made some initial headway, 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 the evening of June 1.
No exclusively Ohio units participated in the Battle of Seven Pines, although McClellan, the Union's commanding general, was an Ohioan.
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 was able to 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.