The Maryland Campaign of 1862
Following his victory at Second Manassas, Gen. Robert E. Lee invaded the Union for the first time during the war. Many in the North were already claiming that the war was a failure. Lee hoped that another Confederate victory, this time on Union soil, would force the North to sue for a negotiated peace and thus win independence for the South. Such a victory might also persuade Great Britain and France to grant diplomatic recognition and, with it, much needed military aid and supplies. One successful victory on Northern soil would do more for Southern Independence than a succession of victories in the south.
Lee's successes had been met with Confederate gains in other areas. In Tennessee, the Confederate Cavalry under the commands of Col. Nathan Bedford Forrest and Col. John H. Morgan successfully wreaked havoc on Union supply lines. Gen. Kirby Smith won a victory at Richmond, Kentucky, and seemed ready to occupy Frankfort. Gen. Braxton Bragg's troops threatened Ohio. The city of Cincinnati was under martial law. For the first time in the North people actually questioned whether or not the Union could survive.
The Battle of Gettysburg has traditionally been referred to as the "High water mark of the Confederacy." Although it certainly was the high water mark of the Army of Northern Virginia, the late summer of 1862 better fits the metaphor for the Confederacy as a whole. The Confederate States of America seemed to be on the verge of achieving independence. At no other time in the war would conditions be as favorable for achieving that independence and at no other time in its short history would the Confederacy instill so much fear in the North, with armies advancing victoriously in both the east and the west.
Invasion of the North might also relieve Virginia of the burden of feeding Lee's army. Across the Potomac River lay the untouched fields of Maryland. Many Southerners considered Maryland a sister state whose citizens might be persuaded to side with the Confederacy. With a Confederate Maryland, the Union capital would be completely surrounded by Confederate territory. In September 1862 Lee tested the true sentiments of the citizens of Maryland.
On Thursday, September 4, 1862, the Army of Northern Virginia crossed the Potomac River and began the Maryland Campaign of 1862. Gen. Lee planned on using Maryland as a stepping stone to Pennsylvania where he hoped to draw the Union Army and fight the decisive battle on ground of his choosing. Lee intended to use the Shenandoah Valley as his line of communication and supply during the campaign. Controlling the northern terminus of the valley, however, was a Union garrison at Harpers Ferry, the "fly in the ointment" of Lee's plans. Lee could not allow the garrison to threaten his supply line. He decided to capture Harpers Ferry. This decision, and the method of accomplishing it, affected the whole campaign.