Confederate General Robert E. Lee's first invasion of the North hinged on eliminating the Harpers Ferry garrison. To do so Lee devised Special Orders 191. He divided his force of 40,000 into four parts. Three columns marched from near Frederick, Maryland, 22 miles northeast of here, to seize the three mountains surrounding Harpers Ferry. The fourth moved north and west toward Hagerstown. Following victory at Harpers Ferry, Lee intended to reunite his army and continue the invasion into Pennsylvania.
Lee assigned Major General "Stonewall" Jackson to command the Harpers Ferry attack. Jackson's columns faced challenging barriers. Long sweeping marches over mountain passes and across the Potomac River required endurance. Once here, "Stonewall's" soldiers had to scale the surrounding heights. Victory demanded coordination, communication, and convergence. Any lapse would enable the Federals to escape.