The Battle of Antietam, fought on September 17, 1862, near Sharpsburg, Maryland, was one of the pivotal conflicts of the American Civil War. It remains the bloodiest single-day battle in American history, with over 22,000 casualties. Union forces, under General George McClellan, clashed with Confederate troops led by General Robert E. Lee. Although the battle ended in a tactical stalemate, it gave President Abraham Lincoln the opportunity to issue the preliminary Emancipation Proclamation, shifting the war’s focus toward ending slavery.
Antietam: The Civil War’s Bloodiest Day
Historical Event | The Battle of Antietam |
Date | September 17, 1862 |
Location | Sharpsburg, Maryland |
Combatants | United States (Union) vs. Confederate States |
Union Commander | Major General George B. McClellan |
Confederate Commander | General Robert E. Lee |
Outcome | Inconclusive (strategic Union victory) |
Significance | Gave Lincoln the opportunity to issue the Emancipation Proclamation |
Total Casualties | Over 22,000 (12,400 Union, 10,300 Confederate) |
Key Areas of Battle | The Cornfield, Bloody Lane, Burnside Bridge |
Aftermath | Lee’s army withdrew to Virginia; McClellan failed to pursue effectively |
Introduction
It could be argued that September 4, 1862, represents the high point of the Confederacy and its attempt to secede from the United States. Over the previous months, southern armies had thwarted the Union’s efforts to capture Richmond. Then, at the Second Battle of Bull Run, Stonewall Jackson had inflicted a crushing defeat on the Union army defending Washington, D.C. Riding this wave of victories, the morale of the southern soldiers was at an all-time high, and the confederate leadership was confident that the south was on the verge of achieving independence from the rest of the Union. Accordingly, on September 4, Lee’s Army of Northern Virginia crossed into Maryland for what they hoped would be the final campaign.
Backdrop to Antietam
- (1) After the Second Battle of Bull Run, the route to Washington for Confederate forces now lay open, but Robert E. Lee knew that he did not have the strength to directly assault the defenses of the northern capital. He devised a plan to bypass Washington and instead invade Maryland. This would be the first time that the Confederacy had invaded the north, and it represented a shift from defense to offense.
- (2) Lincoln faced midterm elections in November, and a successful Confederate campaign in Maryland might discredit him and embolden antiwar northerners into pressuring him to seek peace. Furthermore, Maryland was believed to harbor many southern sympathizers, and Lee hoped that the presence of his army there might provoke the state into switching its allegiance, perhaps even triggering other border states to abandon the Union.
- (3) At the same time, major European powers were actively considering granting political recognition to the Confederacy, which would establish the legitimacy of the Confederacy and likely result in vital material aid. Thus, the march into Maryland on September 4 by Lee’s Army of Northern Virginia might be the final campaign of the Civil War.
The Opponents
- (1) Lee embodied the stereotype of the southern gentleman. He came from one of the most aristocratic families in Virginia. His father had been a renowned commander during the Revolution, was a friend of George Washington, and had served as governor of Virginia. At the outbreak of the Civil War, Lee’s strong allegiance to his home state caused him to decline a high position in the Union army and instead offer his services to the Confederacy.
- (2) After General Joseph Johnston was wounded on June 1, 1862, Lee was appointed commander of the Army of Northern Virginia, operating in the corridor between Washington and Richmond. One of Lee’s best qualities was the confidence and loyalty he inspired in his troops, which enabled him to demand much of them even under conditions of severe hardship. He had a talent for using bold troop movements to outmaneuver and often defeat numerically superior opponents.
- (3) Lee’s undoubted abilities as a general were sometimes undermined by a failure to consider the overall strategic picture; as the war progressed, he clung far too long to a reliance on crude frontal attacks that, even if successful, were wasteful of his limited manpower.
- (4) Lee’s opponent at the Battle of Antietam was George McClellan, whose early career had a number of similarities with Lee’s. McClellan was born into an old, respected Pennsylvania family and attended West Point, where he was a serious and studious cadet. He specialized in engineering and had served with distinction in the Mexican-American War.
- (5) After the shocking northern defeat at the First Battle of Bull Run, McClellan was summoned to Washington and placed in command of the forces defending the capital. Here, McClellan displayed what would be his greatest talents as a general: training and logistics. He vigorously reorganized the army, enforced modern drill, and greatly improved both its discipline and morale.
- (6) Like Lee, he was popular with the soldiers, who appreciated his constant and energetic efforts to improve their conditions. He also applied his industry to erecting a powerful network of fortifications around Washington that were so extensive and well-made that the Confederates would never make a serious effort to break through them.
- (7) Yet McClellan suffered substantial weaknesses as a general: He persisted in vastly overestimating the numbers of his foes, which led him to be overly cautious and slow to attack. He repeatedly failed to exploit opportunities on the battlefield, keeping large contingents of his troops in reserve when they would have been better employed in attacking the enemy.
- (8) These deficiencies caused him to be relieved of command, but when his successor was thrashed at the Second Battle of Bull Run, Lincoln turned to McClellan to rebuild the broken army. Thus, when Lee followed up the victory at Second Bull Run with his invasion of Maryland, it fell to McClellan to oppose him.
The Battle
- (1) At the outset, McClellan fell into a rare opportunity. Lee had written up his plans for the campaign, including detailed instructions and timetables for the movements of each segment of his army—four groups that would converge on a Union garrison at Harpers Ferry—in a document labeled “Special Order 191.” Copies of the order were sent to each of his principal commanders, but one was found lying on the ground by a group of Union soldiers and quickly made its way up the chain of command to McClellan.
- (2) The value of this intelligence was undermined by McClellan’s habitual caution. He squandered his opportunity by deploying his army too sluggishly to catch the elements of Lee’s army and destroy them, with the result that Harpers Ferry fell to Stonewall Jackson, and Lee was able to consolidate most of his scattered army near the town of Sharpsburg. He drew up his forces in a defensive line and prepared to give battle.
- (3) McClellan devised a complicated plan of attack that required close cooperation and timing among the various units in order to maintain continuous pressure, but his orders were too specific, and he failed to apprise commanders of the larger picture, so that units acted independently instead of in concert.
- (4) The battle began at dawn on September 17, with elements of the Union right moving forward against the Confederate left, under the command of Stonewall Jackson. The fighting centered on a field of tall standing corn, across which the southern line stretched. Attackers and defenders exchanged deadly fire at close range, and the field was swept by the artillery of both sides, resulting in a bloodbath that shocked even the veterans.
- (5) The momentum of the battle shifted to the center, where the southerners’ defenses were anchored by a road that formed a natural trench from which the confederates could fire on the advancing Union regiments.
(a) Lee skillfully fed his limited reserves into the fray at just the right moments to save his formations from collapse. When these were used up, he daringly weakened parts of his line to rush troops to the threatened segments.
(b) The Union assaults were just uncoordinated and sporadic enough to enable Lee to play this dangerous game successfully, shuffling his outnumbered men in the nick of time to blunt one attack after another. - (6) Around the road, nearly 6,000 men lay dead or wounded, and the Confederate forces were severely depleted. The formations were shattered, and the defense was reduced to clusters of men still clinging stubbornly to bits of ground. Not only were the Confederates running low on men, but ammunition was scarce as well.
- (7) McClellan had a body of 14,000 men waiting less than a mile from the road who easily could have been ordered forward to exploit the vulnerable Confederate center. As always, however, he was fearful of imaginary Confederate legions and instead gave orders to the generals commanding his reserves to hold their positions.
- (8) Nevertheless, by early afternoon, the irresistible pressure of the Union attacks had pushed the Confederates back from their initial positions in the north and the center. Although forced to give ground, the southern lines had not broken, and the failure to commit reserves caused the Union advance in these parts of the battlefield to lose momentum. The focal point of the battle now shifted to the Union left.
- (9) The Union commander in this sector was General Ambrose Burnside. His 12,000 men were positioned on one side of a steep banked stream spanned by a stone bridge. The Confederate units facing him were well-situated on high ground overlooking the bridge in a network of trenches and rifle pits fronted by fallen trees and other obstacles. By mid-afternoon, Burnside had crossed the narrow bridge and was pursuing the Confederates.
- (10) Lee had nothing left to counter this fresh tide of attackers, and the battle was once again on the verge of a Union victory. But at this crucial moment, the last remaining major division of Lee’s army arrived on the battlefield—General A. P. Hill’s light division. Hill’s division struck the exposed flank of the Union left just as it moved forward against Lee’s main line.
- (11) Despite their numerical advantage on the left, it was the Union forces who gave ground and retreated to their initial positions. Hill’s exhausted men could not pursue, and the long day of fighting finally ended. The dramatic and timely arrival of Hill had saved Lee’s army from destruction.
- (12) The battle of Antietam was the single bloodiest day in the entire Civil War. Stunned by the carnage, the next day, the two armies did nothing, and that night, Lee began withdrawing his forces back toward Virginia. Despite his substantial numerical superiority, his unused reserves, and yet another contingent of 14,000 fresh troops, McClellan let Lee go unmolested.
Outcomes
- (1) Who won the Battle of Antietam? In tactical terms, Lee certainly outmaneuvered McClellan, but in the end, Lee was the one who had to retreat from the battlefield. It is only in retrospect that the true importance of the battle emerges as perhaps the decisive turning point of the war.
- (2) Antietam broke the South’s string of victories and gave the Union army confidence that it could stand up to Lee. It solidified Lincoln’s position and ensured his party’s control of Congress, thus guaranteeing the continued vigorous prosecution of the war. It also ended European flirtation with granting political recognition to the Confederacy, which on its own may have doomed the southern cause.
- (3) Finally, Antietam provided the victory that Lincoln had been waiting for to issue the Emancipation Proclamation. Although mainly symbolic, this act fundamentally transformed the nature of the war from a struggle about states’ rights or economics into a moral crusade being fought for the very soul of the nation.
Conclusion
The Battle of Antietam marked a critical turning point in the American Civil War. Although tactically inconclusive, it was a strategic victory for the Union as it halted General Lee’s invasion of the North. The battle’s immense casualties, the bloodiest of any single day in American history, underscored the war’s brutality. Most importantly, Antietam provided President Lincoln with the opportunity to issue the preliminary Emancipation Proclamation, redefining the war’s purpose and paving the way for the abolition of slavery. Despite missed opportunities for a decisive Union victory, Antietam shifted the war’s momentum in favor of the North.
(FAQ) about The Battle of Antietam
1. Why is the Battle of Antietam significant?
The Battle of Antietam is significant because it halted General Robert E. Lee’s first invasion of the North. It also provided President Abraham Lincoln with the opportunity to issue the preliminary Emancipation Proclamation, which changed the focus of the war toward ending slavery.
2. What were the key areas of fighting during the battle?
The three key areas of the battle were The Cornfield, where intense fighting occurred early in the day, Bloody Lane, a sunken road that became a death trap for Confederate soldiers, and Burnside Bridge, where Union forces eventually broke through Confederate defenses.
3. How many casualties were there at the Battle of Antietam?
There were over 22,000 casualties, making it the bloodiest single-day battle in American history. The Union suffered around 12,400 casualties, while the Confederates had approximately 10,300.
4. Who commanded the Union and Confederate forces at the Battle of Antietam?
Union forces were commanded by Major General George B. McClellan, while Confederate forces were led by General Robert E. Lee.
5. What was the outcome of the battle?
The battle ended inconclusively, but it is considered a strategic victory for the Union because Lee’s forces withdrew to Virginia. However, McClellan was criticized for not pursuing the retreating Confederate army more aggressively.
6. How did the Battle of Antietam impact the Civil War?
The battle shifted the momentum in favor of the Union and provided President Lincoln with the political leverage to issue the preliminary Emancipation Proclamation. This document redefined the purpose of the war to include the abolition of slavery, in addition to preserving the Union.
7. Why is the Battle of Antietam known as the bloodiest single-day battle in American history?
The battle resulted in an unprecedented number of casualties—over 22,000 in just one day. This staggering loss of life made it the bloodiest day of fighting in American history.
8. Did the battle lead to any immediate changes in Union leadership?
While McClellan won a strategic advantage, his failure to decisively pursue Lee’s army led to his eventual removal from command by President Lincoln. Lincoln was frustrated by McClellan’s cautious approach and lack of aggressive follow-up.