The Peninsula Campaign was a series of battles during the American Civil War. The campaign happened from March to July 1862. The Union Army of the Potomac, commanded by George B. McClellan, tried to capture the Confederate capital of Richmond, Virginia by moving westward on the Virginia Peninsula. The Confederate Army of Northern Virginia, commanded by Joseph E. Johnston, tried to stop McClellan. After Johnston was wounded on May 31st at the Battle of Seven Pines, Robert E. Lee took command of the army. Lee then attacked McClellan during the Seven Days Battles. After the battles, McClellan's army was transferred back to Washington, D.C.