The Peninsula Campaign (also known as the Peninsular Campaign) of the American Civil War is a major Union operation launched in southeastern Virginia from March through July 1862, the first large-scale offensive in the Eastern Theater.

The operation, commanded by Maj. Gen. George B. McClellan, is an amphibious turning movement against the Confederate States Army in Northern Virginia, intended to capture the Confederate capital of Richmond.

McClellan is initially successful against the equally cautious General Joseph E. Johnston, but the emergence of the more aggressive General Robert E. Lee turns the subsequent Seven Days Battles into a humiliating Union defeat.

McClellan landshis army at Fort Monroe and movs northwest, up the Virginia Peninsula.

Confederate Brig. Gen. John B. Magruder's defensive position on the Warwick Line catches McClellan by surprise.

His hopes for a quick advance foiled, McClellan orde his army to prepare for a siege of Yorktown.

Just before the siege preparations are completed, the Confederates, now under the direct command of Johnston, begin a withdrawal toward Richmond.

The first heavy fighting of the campaign occurs in the Battle of Williamsburg, in which the Union troops manage ome tactical victories, but the Confederates continue heir withdrawal.

An amphibious flanking movement to Eltham's Landing is ineffective in cutting off the Confederate retreat.

In the Battle of Drewry's Bluff, an attempt by the U.S. Navy to reach Richmond by way of the James River is repulsed.

As McClellan's army reachea the outskirts of Richmond, a minor battle occurs at Hanover Court House, but it is followed by a surprise attack by Johnston at the Battle of Seven Pines or Fair Oaks.

The battle is inconclusive, with heavy casualties, but it has lasting effects on the campaign.

Johnston is wounded by a Union artillery shell fragment on May 31 and replaced the next day by the more aggressive Robert E. Lee, who reorganizes his army and prepares for offensive action in the final battles of June 25 to July 1, which are popularly known as the Seven Days Battles.