Why Lee Invaded Maryland

Lee's greatest objective was that a victory in the North could possibly gain diplomatic recognition from Europe and bring England and France to the aid and assistance of the South. Such a victory might cause the people of the North to question President Abraham Lincoln's leadership and force him to sue for peace.

Just one week after the Second Battle of Bull Run, General Robert E. Lee decided it was time to take the war into the North. By marching his victorious army into Maryland, Lee had several objectives. He wanted to maintain the momentum achieved with his stunning victory at Bull Run, which left the retreating Union army in chaos. By advancing into Maryland, Lee could relieve Virginia of enemy occupation. He knew the Union army would have to mirror his movements and take up defensive positions in front of Washington and Baltimore.

Lee hoped that by marching into Maryland he could rally the Border State for the Southern cause. He could perhaps influence the upcoming Congressional Elections and persuade more Democrats (who favored peace) to outvote the Republican majority in the House and demand an end to the Civil War.

Logistically, moving his army into the unharvested, virgin countryside of western Maryland would provide new food supplies for Lee's hungry soldiers, and the merchant stores in Frederick could resupply his troops with new clothing and shoes. September and October mark the key harvest months. Without Union armies impeding them, the Southern farmers could gather their harvests and subsequently feed Lee's armies during the winter.

On Thursday morning, September 4, 1862, the dirty, ragged Army of Northern Virginia splashed across the shallow fords of the Potomac River just north of Leesburg to the strains of "Maryland, My Maryland." By midmorning, Saturday, September 6, General "Stonewall" Jackson's advance force of 5,000 men marched down Market Street in Frederick and made camp on the north side of town. The remainder of Lee's 40,000-man army soon followed.

Upon his arrival in town, Lee designed the Proclamation to the People of Maryland, inviting them to side with the Southern movement. For the next several days Lee's troops, upon strict orders not to pillage, bought all the food, shoes and clothing they could find at the stores. But soon it became obvious that the citizens of Frederick, though polite, had little sympathy for the Southern cause.

So Lee comprised a new set of plans. He would divide his forces into four sections, sending Gen. Jackson with six divisions of 22,000 men to eliminate the 12,000-strong Federal garrison at Harpers Ferry to the southwest. The remaining three divisions of Lee's forces--18,000 men, under Gen. James Longstreet- would move northwest over the Catoctin and South Mountain ranges to Boonsboro and Hagerstown, a distance of 25 miles.

Later, Jackson would rejoin Lee and Longstreet at Hagerstown. Then, using these mountain ranges to protect his right flank, Lee could move his combined Confederate forces northeast along the rail line to Harrisburg, the capital of Pennyslvania and a key rail center for the Union. Early on Wednesday morning, September 10, Lee's forces began leaving Frederick to carry out their assignments.

Three unforeseen events, however, would disrupt Lee's plans. General George McClellan would reorganize the Army of the Potomac in days, rather than weeks as Lee expected, and arrive in Frederick on Friday, September 12th. Second, the garrison at Harpers Ferry, rather than fleeing, was ordered to stand until reinforcements could arrive. Third, an official copy of Lee's Special Orders No. 191--wrapped around three cigars--would be found by a Union private in an abandoned Confederate campsite the next day.

When Lee learned that McClellan's army was moving westward from Frederick, he realized the peril of his divided forces. He rapidly sent troops to block the three main passes over South Mountain, providing sufficient time to concentrate the majority of his forces in a defensive position around Sharpsburg, six miles to the southwest of Boonsboro. Concurrently, McClellan's 85,000 men gathered on the east bank of the Antietam Creek. And thus, late on September 16, the dye was cast for the battle that would begin at sunrise the next morning; the battle that would become known as the bloodiest day in America's history.

Sources: Official Records of the Union and Confederate Armies; Antietam Battlefield Board; Antietam National Battlefield Park; National Park Service.

Recommended Reading: The Antietam Campaign (Military Campaigns of the Civil War). Description: The Maryland campaign of September 1862 ranks among the most important military operations of the American Civil War. Crucial political, diplomatic, and military issues were at stake as Robert E. Lee and George B. McClellan maneuvered and fought in the western part of the state. The climactic clash came on September 17 at the battle of Antietam, where more than 23,000 men fell in the single bloodiest day of the war. Continued below...

Approaching topics related to Lee's and McClellan's operations from a variety of perspectives, numerous contributors to this volume explore questions regarding military leadership, strategy, and tactics, the impact of the fighting on officers and soldiers in both armies, and the ways in which participants and people behind the lines interpreted and remembered the campaign. They also discuss the performance of untried military units and offer a look at how the United States Army used the Antietam battlefield as an outdoor classroom for its officers in the early twentieth century. Also available in paperback: The Antietam Campaign (Military Campaigns of the Civil War)

Highly Recommended Reading (Editor's Pick): The Maryland Campaign of September 1862: Ezra A. Carman's Definitive Study of the Union and Confederate Armies at Antietam (Hardcover). Description: Completed in the early 1900s, The Maryland Campaign of September 1862 is still the essential source for anyone seeking understanding of the bloodiest day in all of American history. As the U.S. War Department’s official expert on the Battle of Antietam, Ezra Carman corresponded with and interviewed hundreds of other veterans from both sides of the conflict to produce a comprehensive history of the campaign that dashed the Confederacy’s best hope for independence and ushered in the Emancipation Proclamation. Nearly a century after its completion, Carman's manuscript has finally made its way into print, in an edition painstakingly edited, annotated, and indexed by Joseph Pierro. The Maryland Campaign of September 1862 is a crucial document for anyone interested in delving below the surface of the military campaign that forever altered the course of American history. Continued below...

Editorial Reviews:

Ted Alexander, Chief Historian, Antietam National Battlefield

"The Ezra Carman manuscript is the definitive study of that bloody September day in 1862. By editing it Joseph Pierro has done a tremendous service to the field of Civil War studies. Indeed, this work is one of the most important Civil War publications to come out in decades."

 

James M. McPherson, author of Crossroads of Freedom: Antietam

"Many accounts of Civil War battles were written in the decades after the war by soldiers who had participated in them. None rivals in accuracy and thoroughness Ezra Carmen's study of the battles of South Mountain and Antietam, in which he fought as colonel of the 13th New Jersey. Students of the 1862 Maryland campaign have long relied on this manuscript as a vital source; Joseph Pierro's scrupulous editorial work has now made this detailed narrative accessible to everyone. A splendid achievement."

  

Jeffry D. Wert, author of The Sword Of Lincoln: The Army of the Potomac

"At last, after a century, Ezra A. Carman's The Maryland Campaign of September 1862 has received the attention it deserves. A Union veteran, Carman authored a remarkable primary study of the critical operations that ended along Antietam Creek. Editor Joseph Pierro has given students of the Civil War and American history a most welcome and long overdue book."

 

Edwin C. Bearss, author of Fields of Honor: Pivotal Battles of the Civil War

"My introduction to the Ezra A. Carman Papers at the Library of Congress and National Archives came in the spring of 1961. I was astounded and amazed by their depth and scope. The correspondence, troop movement maps, etc, along with Carman's unpublished manuscript on the Antietam Campaign constitutes then as now an invaluable legacy to the American people by Carman and the veterans of Antietam. But for too long that resource has only been available to the general public as microfilm or by traveling to Washington. Now thanks to the publishers and skilled, knowledgeable, sympathetic, but light-handed editor Joseph Pierro, an annotated copy of Carman's masterpiece The Maryland Campaign of September 1862 will be available to the public."

 

William C. Davis, author of Look Away! A History of the Confederate States of America

"Joseph Pierro brings into the open one of the great and largely unknown masterworks of Civil War history. Ezra Carman's work on Antietam is a fountainhead for study of that pivotal battle, written by a man who was in the fight and who spent most of his life studying and marking the battlefield. No student can afford to ignore this stunningly thorough and brilliantly edited classic."