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Should anyone consider “civil war” over the outcome, one way or the other, of the presidential election that is six weeks from now, let’s look at the Battle of Antietam. It took place 162 years ago this month and is often referred to as the bloodiest day of Americans killing Americans. In addition, some historians think this battle was more pivotal than Gettysburg 10 months later.
On September 13, 1862, just outside Frederick, Maryland, two Union soldiers, John Bloss and Burton Mitchell, found an abandoned Confederate camp. That the rebels were in Maryland was interesting enough, but the real surprise was the discovery of three cigars wrapped in a piece of paper. That paper turned out to be Special Order 191, which was General Robert E. Lee’s strategy for attacking the North. Especially beneficial to the Union Army was the information that Lee had divided his Army of Northern Virginia into five groups, making each one more vulnerable to attack.
This cigar wrapping should have been a godsend to Gen. George B. McClellan, the Union’s top general and commander of the Army of the Potomac. But true to form, he dithered and took 18 hours to mobilize his forces. Meanwhile Lee, who had learned of the Yankee discovery of Special Order 191, gathered his groups back together. An enormous Union opportunity had been squandered.
Over the next several days the armies inched toward each other. Lee hoped that a successful invasion of the North would be a knockout blow after 19 months of war. The Union needed a victory too. President Abraham Lincoln had written the Emancipation Proclamation, but after several recent Union losses, including the Second Battle of Bull Run, he needed some good news to strengthen his position of freeing slaves. Politically, in less than two months there would be midterm elections and the Republican Party’s majority in Congress might not survive them. Frustrated with Lincoln’s policies and the course of the war, Democrats had launched an anti-war campaign, hoping to take power and possibly negotiate peace with the South. Another consequence of victory could be Great Britain and/or France throwing their support to the South.
After Lee thwarted the plan of McClellan to lay siege to Richmond in the Peninsula Campaign in the spring and summer of 1862, McClellan retreated. Hoping to take advantage of the Union’s low morale and seeming ineptitude, Lee chose to push his army north across the Potomac and into Maryland where they soon occupied the town of Frederick. On September 9, Lee had issued Special Order 191 defining his “Maryland Campaign.” But four days later, McClellan had Lee’s plans in his hands. He reportedly exclaimed, “Here is a paper with which, if I cannot whip Bobby Lee, I will be willing to go home.”
The Battle of Antietam began at dawn on September 17, 1862 — a Wednesday — as the fog lifted. The units of Generals James Longstreet and A.P. Hill formed the Confederate right and center flanks to the west of Antietam Creek, while Generals Stonewall Jackson’s and John G. Walker’s units formed the Confederate left flank. All of Lee’s troops were worn out and hungry, and many were sick. They watched and waited as McClellan’s army assembled along the creek’s east side. Union forces outnumbered Confederates by two to one, although McClellan thought Lee’s forces were much larger. Troops from both sides faced off across a 30-acre cornfield.
Union troops fired first at the Confederate left flank and the carnage began. The rebels ferociously fought off assault after assault to prevent being overrun, turning the cornfield into a massive killing field. Just eight hours in, there were over 15,000 casualties.
Near the center of the battlefield, another site of slaughter was a farm lane known as the “Sunken Road,” where Hill’s division of approximately 2600 men had piled fence rails along the road’s embankment to fortify their position against Union Major General William H. French’s 5500 approaching troops. When French’s troops arrived, fighting ensued at close range. Three hours later, Union troops had pushed the Confederates back and over 5000 men were either dead or injured. The fighting was so gory Sunken Road earned a new name: Bloody Lane.
For more than three hours, fewer than 500 Confederate soldiers held Lower Bridge against multiple assaults by Union General Ambrose Burnside’s Ninth Corps. After Burnside’s troops finally took the bridge and had the Confederate right flank in sight, rebel reinforcements arrived and pushed them back.
As night fell, according to an account on History.com, “Thousands of bodies littered the sprawling Antietam battlefield and both sides regrouped and claimed their dead and wounded. Just twelve hours of intense and often close-range fighting with muskets and cannons had resulted in around 23,000 casualties, including an estimated 3650 dead.”
The next day, Lee began the painstaking job of moving his ravaged troops back to Virginia. While this was going on, McClellan, apparently stunned by the number of casualties, did nothing. Despite having a numerical advantage, he allowed Lee to retreat without firing a shot. He had, at least, prevented a Confederate win on Union soil.
His boss was not so sanguine. President Lincoln thought McClellan missed a great opportunity to kick the Army of Northern Virginia while they were down and potentially end the war. After the young and hesitant general repeatedly refused Lincoln’s order to pursue Lee’s retreating troops, the President fired him. General Burnside replaced McClellan, who two years later would unsuccessfully challenge Lincoln in the presidential election.
Many military historians consider the Battle of Antietam a stalemate. Even so, the Union claimed victory. And keeping Confederates in their southern box enabled President Lincoln to eventually release his Emancipation Proclamation. Ironically, it did not free slaves in Maryland because it only applied to slaves in rebel states. Still, it endorsed the idea that the war was not just about states’ rights but also ending slavery.
The Union’s claim of victory at Antietam helped the Republicans hold the House in the mid-term elections. It also ended any hope of France and Great Britain acknowledging the Confederacy and coming to its aid. This further isolated the Confederacy and made it harder for it to re-supply its troops and citizens. The bloodiest day in American history had its bright spots and the Union fighters, at least, had not died in vain.
Originally published on Tom Clavin’s The Overlook.