In 1862, after Robert E. Lee had taken over command of Confederate forces, he decided to invade the North, particularly the states of Maryland of Pennsylvania. Lee believed an invasion of Maryland would incite the people of that state, still in Union control, to rebel against the United States. He also believed an invasion of the North would damage the Union morale, and he believed he could garner critical food and supplies from the unspoiled farms that had not been torched by battles as those in Virginia had. He also sought to destroy the Baltimore & Ohio Railroad which supplied Washington D.C.
As Lee’s Army marched through the Shenandoah Valley and into Maryland, he split his main forces, sending Stonewall Jackson’s brigade to Harper’s Ferry for the purposes of commandeering the city’s federal arsenal full of ammunition and weapons, but also to open a supply line to Virginia. Union Colonel Dixon Miles was in charge of Harper’s Ferry and concentrated his force in the city, rather than spreading them among the high hills surrounding it. On September 13, 1862, Confederate forces arrived and scattered the scant Union defenses in the hills, leaving them open to Confederate occupation. Meanwhile, Confederate General Stonewall Jackson made preparations for an attack on Harper’s Ferry and positioned his artillery around the city. Jackson was able to place fifty pieces of artillery on a high hill overlooking Harper’s Ferry known as Maryland Heights and at the base of a hill known as Loudoun Heights. Jackson commanded General A.P. Hill to move along the west bank of the Shenandoah River for an assault on the Union left flank. On the morning of September 15, Jackson ordered his artillery to fire and viciously bombarded Harper’s Ferry while simultaneously ordering an infantry charge. Colonel Miles quickly realized he had no chance and began surrender negotiations. Before he could officially surrender, however, he was killed by an artillery shell. Confederate forces would take nearly 12,000 Union prisoners making it the largest surrender for the Union in the entire Civil War. Because of the poor tactics and preparation under the leadership of Colonel Miles, the outcome of the battle came quickly, resulting in less than 500 total casualties.
From Harper’s Ferry, Jackson would rush to join General Robert E. Lee at Sharpsburg, Maryland for what would become the infamous Battle of Antietam.