The American Battlefield Trust’s map of the Peninsula Campaign of 1862
From April 4 to June 1, 1862, Maj. Gen. George B. McClellan’s Army of the Potomac moved up the Virginia peninsula between the York and James Rivers toward Richmond. After the fall of Portsmouth and the scuttling of the ironclad CSS Virginia May 10-11, the Union navy could safely advance up the rivers and protect McClellan’s flanks. Gen. Joseph E. Johnston, commanding the army defending the Confederate capital, attacked McClellan on June 1 at Seven Pines (also known as Fair Oaks), but was severely wounded. His replacement, Gen. Robert E. Lee, launched the Seven Days battles later in June that ultimately pushed McClellan’s army back from Richmond.