The South’s invasion into the North was to serve several goals, park officials said.
Lee was hoping to recruit more soldiers in Maryland because it was a slave state; he wanted to take the war into Pennsylvania to sway residents of the North to vote in the upcoming congressional elections for politicians who were against the war, thus weakening Lincoln’s government; and he wanted a victory to garner European support so European leaders might broker a peace, park officials said.
The invasion also would relieve Virginia of occupation so Shenandoah Valley farmers could bring in the harvest, which would help feed the Confederate Army, said Dennis Frye, the park’s chief historian.
“The South desperately wanted and needed the recognition of European powers,” said David Fox, park ranger at Harpers Ferry National Historical Park.
A major Southern victory could have led to British mediation, Frye said.
At this time, the Confederate Army had a 1,000-mile front from Mississippi to Maryland with a coordinated military offensive, Frye said.
“At no other time during the war was the Union in greater peril of becoming a permanent divided state,” said Frye, a Civil War historian whose new book, “September Suspense” elaborates on that theme.
Frye said, “Lee knew this was the ideal opportunity to take advantage of the chaos in the northern army and to exploit political opportunity in the upcoming fall elections.
“Lee realized that this was the best hope of a Confederacy to attain its independence.”
For Lee’s invasion to work, he needed to use the Shenandoah Valley as a communication and supply line for the army, Fox said.
Lee stopped his forces to the north, east and south of Frederick, Md., to rest, reorganize and replenish his army, Frye said. From the Frederick area, the Confederate Army could threaten both Baltimore and Washington.
Union Maj. Gen. George B. McClellan had adopted a defensive posture to protect the cities in that area.
Lee was “baffled” when the garrison at Harpers Ferry didn’t withdraw north, parallel to his invasion, Frye said.
Special Orders 191
Lee issued Special Orders 191, which described how he was sending three columns, totaling about 28,000 men, to surround Harpers Ferry until the Union garrison was destroyed or captured. Lee’s orders called for two-thirds of his army to march on Harpers Ferry starting Sept. 10, and for the Harpers Ferry garrison to be eliminated by Sept. 12, Frye said.
When Lee moved out of the Frederick area, McClellan was able to move from his defensive posture, Frye said. Having already split his army, McClellan sent the southern prong, which was nearest to the Potomac River, to relieve the Harpers Ferry garrison, Frye said.
On Sept. 13, the northern prong of McClellan’s army camped near the Monocacy River southeast of Frederick, on the same grounds where Confederate soldiers had been a few days earlier, and it was there that Union soldiers found a copy of Lee’s Special Orders 191, Frye said.
“It’s almost unbelievable. This is truth stranger than fiction. An entire copy of battle plans and someone dropped it on the battlegrounds,” Fox said.
The lost orders gave McClellan an opportunity to move aggressively against Lee’s scattered army with the hope it could relieve the garrison at Harpers Ferry and trap Lee at Hagerstown, Frye said.
Surrounding Harpers Ferry
To seize control of Harpers Ferry, Lee sent two-thirds of his army, under the command of Maj. Gen. Thomas “Stonewall” Jackson.
Those soldiers approached the low-lying town from three directions, two of which were from the high ground of the edge of the Blue Ridge Mountains — Maryland Heights and Loudoun Heights.
Today, Loudoun Heights is the border between Loudoun County, Va., and Jefferson County, W.Va., Fox said.