On the 150th Anniversary of Antietam, the Horror of America’s Deadliest Day

Then, again.
Sept. 17 2012 11:52 AM

The Horror of Antietam

America’s deadliest day, as witnessed by Oliver Wendell Holmes, William McKinley, Rutherford B. Hayes, and Clara Barton.

Antietam Battlefield Photos

A misty rain shrouded Antietam Creek as Pvt. David L. Thompson and other footsore soldiers from the 9th New York Infantry took their places on the Union line and unrolled their blankets. It was Sept. 16, 1862, a night marked by the sputtering fire of nervous pickets, the cursing of men tripping over objects in the dark (including a regimental dog), and waves of panic.

“We sat down and watched for a while the dull glare on the sky of the Confederate campfires behind the hills,” Thompson wrote. “We were hungry, of course, but as no fires were allowed, we could only mix our ground coffee and sugar in our hands and eat them dry. ... There was something weirdly impressive yet unreal in the gradual drawing together of those whispering armies under cover of the night—something of awe and dread.”

Two great armies were steeling themselves for what would become the deadliest one-day battle in American history. That 12-hour fight would change the course of the war, determine the fate of 4 million slaves and shock the public. Thanks to some of the first—and still most haunting—battlefield photographs in history, people would see the reality of the fratricide that until then had been a distant abstraction.

North and South fought in the open at close quarters—usually no more than 300 yards apart—with no protective earthworks to soften the blows. Gen. Robert E. Lee, leading thousands of tattered, battle-hardened Confederate troops into enemy territory for the first time, tried for a desperate knockout punch that would bring the two-year-old conflict to a swift conclusion. Maj. Gen. George B. McClellan, charged with fending off the Confederate invasion threatening the capital in Washington, summoned the largest army yet to face Lee’s forces and tried to pin his adversary at Antietam, with the Potomac River at Lee’s back.

The clash was one of the worst days in a long war known for its carnage. Because the literacy rate in both armies was quite high—above 90 percent—the survivors wrote letters and diaries detailing their experiences, and we have an excellent record of what transpired at Antietam. Time has softened the horror, but even today the photographs and remembrances of those who were there offer a glimpse of a national tragedy written in smoke and blood.

The morning of Sept. 17 opened with a tremendous crash as opposing batteries traded blows across the creek. Maj. Gen. Joseph “Fighting Joe” Hooker and some 8,600 men of the Union First Corps came boiling out of the woods about 6 a.m. and headed for Dunker Church. The squat white building marked the northern end of the Confederate line, held by Maj. Gen. Stonewall Jackson’s troops. “The Federals in apparent double battle line were moving toward us at charge bayonets, common time,” wrote a veteran of the Stonewall Brigade, “and the sunbeams falling on their well-polished guns and bayonets gave a glamour and a show at once fearful and entrancing.”

To reach the church, Hooker’s troops had to cross open ground, plunge into a thickly planted cornfield and emerge on the far side. But the cornfield erupted in a torrent of fire from Confederates hidden among the stalks.

As the first of Hooker’s troops fell in the corn, others poured in to replace them, scrambling around the dead and driving for the church. “Men, I can not say fell; they were knocked out of the ranks by dozens,” wrote Maj. Rufus Dawes of the 6th Wisconsin Regiment. “But we jumped over the fence, and pushed on, loading, firing and shouting as we advanced. There was, on the part of the men, great hysterical excitement, eagerness to go forward and a reckless disregard of life.” They pursued Jackson’s troops toward Hagerstown Pike, riddling them from behind as the Confederates tried to clamber over the roadside fences.

To stiffen his lines, Jackson summoned Brig. Gen. John Bell Hood’s troops, who were cooking the first hot meal they had eaten in days. Hood’s men put their bread aside, took up muskets, and streaked toward the battle, screeching as they went. “I have never seen a more disgusted bunch of boys and mad as hornets,” a soldier from Hood’s 2,300-man division recalled. The hungry Rebels smashed into Hooker’s forces, mowing down Union troops “like a scythe running through our line,” one Federal survivor wrote. Surging across the cornfield, Hood’s counterattack regained most of the bloody ground lost earlier that morning—with more than 60 percent of his men dead, wounded, or missing. When Hood returned from the front, trailed by a remnant of his command, someone asked where his troops were. “Dead on the field,” he said.

Two other Union corps fed fresh soldiers into the fight as Lee desperately stripped other parts of his line to meet each new thrust. By 10 a.m., the cornfield had changed hands 15 times. “Every stalk of corn in the greater part of the field was cut as closely as could have been done with a knife,” Hooker recalled, “and the slain lay in rows precisely as they had stood in their ranks a few moments before.” Riding among his men on a big gray horse, the general made an easy target. He was shot in the foot and put out of action that morning.

He was one of almost 10,000 casualties from the opening hours of fighting; another was a recent Harvard graduate, Capt. Oliver Wendell Holmes Jr. of the 20th Massachusetts, shot through the neck and left for dead on the field. Holmes recovered, finished the war with distinction, and became a Supreme Court justice. But he admitted that after Antietam, “the world never seemed quite right again.”

McClellan planned to dismember Lee’s army piecemeal, first hitting hard on the Confederate left, then breaking Lee’s right to block his escape across the Potomac, then throwing four fresh divisions into the Rebel center for the coup de grace. It was a sound plan, but McClellan’s offensives were poorly coordinated. McClellan stayed well to the rear, keeping some 20,000 of his men in reserve. Had he pressed a lopsided advantage in numbers, he might have broken through and annihilated the Army of Northern Virginia; but he held back, convinced by faulty intelligence and vivid imagination that Lee’s forces outnumbered his own. At Antietam, McClellan, known for his caution and blustering talk, cemented his reputation for being the most tentative of generals.

Union Maj. Gen. Ambrose E. Burnside received orders to press Lee’s army below Sharpsburg, where a humpbacked bridge spanned Antietam Creek. Burnside held the advantage of 12,500 troops of his 9th Corps against some 4,000 Georgians from Maj. Gen. James Longstreet’s command. But the Confederate infantry, backed by two batteries of artillery in steep bluffs west of the creek, picked off hundreds of Union soldiers as they emerged from the trees and tried to cross the bridge, while others were shot or drowned fording the stream. It took Burnside’s troops three hours to cross the creek.

Bodies of Confederate dead gathered for burial at Antietam.
Bodies of Confederate dead gathered for burial at Antietam. See more photos here.

Alexander Gardner/Library of Congress.

Many recruits, facing fire for the first time, turned and ran; two deserters from the newly formed 16th Connecticut Infantry kept going until they reached England, where they sat out the war. The urge to flee seemed perfectly human, even to Pvt. Thompson, the coffee-eating New Yorker, who kept moving forward as Minié balls buzzed by his head and comrades fell around him. “The truth is,” he wrote, “when the bullets are whacking against tree trunks and solid shots are cracking skulls like eggshells, the consuming passion in the breast of the average man is to get out of the way. Between the physical fear of going forward and the moral fear of turning back, there is a predicament of exceptional awkwardness from which a hidden hole in the ground would be a wonderfully welcome outlet.”

While the battle of the bridge slowly unfolded below Sharpsburg, an intense struggle broke out north of the town. At the center of Lee’s lines, some 10,000 Union troops tried to break through a Confederate front defended by 7,000 men.

The Rebels made their stand in an old farm lane known as the Sunken Road, eroded below the level of the surrounding fields by decades of wagon traffic. The trench gave the Confederates a protected position from which they unleashed fire on wave after wave of advancing Federals. The Yankees had to surmount the blind side of a knoll about 100 yards in front of the lane and cross exposed land above the Sunken Road, their heads silhouetted against the sky. They looked like figures in a shooting gallery. “Go away, you black devils! Go home!” the Rebels shouted, taking aim as each ragged line crested the hill. This part of the battle, which raged for three hours, was perhaps the most concentrated clash of the morning.

Within the tumult, a soldier from the 1st Delaware Infantry saw a comrade staggering around with both eyes shot out and pleading “for the love of God” for someone to end his agony. A lieutenant heard his appeal, verified its sincerity and coolly shot the blind man in the brain. “It was better thus,” the lieutenant said. Then a solid shot took the lieutenant’s head off, consigning another recruit to the army of the dead.

As the stricken cried out for mothers they would never see again, a woman in a bonnet secured by a red ribbon wandered among the fallen, binding their wounds and offering comfort as shot and shell gouged the earth around her. Clara Barton, a U.S. Patent Office clerk, was a self-appointed nurse who found her way to Antietam at the height of the fracas. As she kneeled to offer water to a wounded man, she felt a tug at her sleeve—it was a bullet, which ripped through her dress without touching her. It smacked into her patient, killing him outright. Unfazed, she straightened up, looked around for another soldier in trouble and went to work on him. The future founder of the American Red Cross never mended her torn blouse. “I wonder if a soldier ever does mend a bullet hole in his coat?” she said later.

After several hours, Union troops rushed forward to pour fire up and down the Sunken Road, knocking down hundreds of men. The dead and wounded tumbled together, lining the bottom of the declivity that would be known thereafter as Bloody Lane. The surviving Rebels scrambled out of the pit and Federals took possession, horrified by what they found. “In this road there lay so many dead rebels that they formed a line which one might have walked upon as far as I could see,” wrote Lt. Thomas L. Livermore of the 5th New Hampshire Infantry.

By 1 p.m., Lee’s center had broken. The survivors of Bloody Lane scuttled for the rear and formed a new defensive line on a ridge to the west. “We were already badly whipped and were only holding our ground by sheer force of desperation,” Longstreet recalled. Yet the thin gray line held. McClellan never tested it, husbanding his reserves for an imagined Rebel counteroffensive. “It would not be prudent to make the attack,” he said, overruling officers eager to swoop in for the kill.

Exhausted, both sides fell silent and glared at one another across the blood-soaked center. But even as the clamor subsided in that sector, the distant barking of musketry and the rumble of artillery boiled up from the south, where Burnside’s men had won the bridge—since known as Burnside’s Bridge—and begun clawing their way to Sharpsburg, uphill all the way.

That end of the Confederate line, stripped to the bone earlier in the day to defend the Dunker Church and Bloody Lane, was down to nothing, with no reserves in sight. Bluecoats converged on the town, threatening the Rebels’ path home. Lee, drawn up on a knoll at the other end of Sharpsburg, could see disaster brewing. But then he noticed a cloud of dust building over the Potomac River crossing and a mass of men tromping toward Sharpsburg.

“Whose troops are those?” he asked, turning to a lieutenant. The lieutenant raised a telescope, peered at the column and announced: “They are flying the Virginia and Confederate flags, sir.”

One of Lee’s boldest commanders, Maj. Gen. A. P. Hill, conspicuous in his red battle shirt, was rushing from Harper’s Ferry to the Antietam fight with more than 3,000 men behind him. It was after 3:30 p.m. when Hill’s troops hurled into the flank of Burnside’s 9th Corps. The Union lines gave way grudgingly, falling back over ground won just hours before. Some Federals were bewildered to see that many of their attackers wore the Union blue, which Confederates had exchanged for their ragged uniforms on the way out of Harper’s Ferry. “Don’t fire on your own men!” cried one of the Rebels, swooping down on unsuspecting soldiers from an Ohio regiment.

As the fighting swirled around Sharpsburg, a Union commissary sergeant named William McKinley came flying across the hills, driving a wagon loaded with food and coffee for comrades of the 23rd Ohio Regiment. They recharged themselves and gave thanks to Sgt. McKinley, who was promoted by his commanding officer, Col. Rutherford B. Hayes, for his bravery that day. In time both men would become president of the United States and strong advocates of reunion between North and South.

When the sun went down on Sept. 17, neither side occupied new ground. The battle left almost 23,000 dead, wounded, captured, or missing, a record of loss unmatched in American history. The death toll was more than 3,600 for both sides, even greater than the 2,500 who died in the D-Day invasion more than eight decades later. McClellan suffered more casualties, 12,400 to Lee’s 10,300, but the proportional loss was greater for Lee’s smaller army. Even so, the Southern leader audaciously kept his own shattered force on the field after the great battle, reforming his lines and taunting the Yankees.

Both sides had won, both had lost: Lee had invaded hostile country and held the field. But his plans for a Maryland campaign were in tatters, his command reeling from deaths and injuries through the ranks. Britain, which had been on the point of recognizing the Confederacy before Antietam, refrained from doing so afterward. Lee stole away in the dark on Sept. 18, leading the Army of Northern Virginia home to recuperate. McClellan let him go largely unmolested, relieved that Lee had been deflected from Pennsylvania and ejected from Maryland. Washington, D.C., was safe.

Along Antietam Creek, soldiers sorted through the wreckage and tallied the grim cost of Sept. 17. “The excitement of battle comes in the day of it, but the horrors of it two or three days after,” wrote Capt. Samuel Fiske of the 14th Connecticut. He told of bloated bodies and “hundreds of horses too, all mangled and putrefying, scattered everywhere! Then there are the broken gun-carriages, the wagons and thousands of muskets, and all sorts of equipments, and clothing all torn and bloody ... the trees torn with shot and scarred with bullets, the farm-houses and barns knocked to pieces and burned down, the crops trampled ... the whole country forlorn and desolate.”

To read of such scenes was sobering; to see them, transformative. Within days of the fighting, just as burial parties began to harvest the dead, the impresario Mathew Brady dispatched Alexander Gardner and James F. Gibson to record scenes from the battlefield.* Their photographs, documenting the devastation of the cornfield, the Bloody Lane, and elsewhere, were displayed in Brady’s New York studio, where many Americans faced the horrors of war for the first time.

“The dead of the battle-field come up to us very rarely, even in dreams,” a reporter for the New York Times wrote after a visit to Brady’s studio. “Mr. Brady has done something to bring home to us the terrible reality and earnestness of war. If he has not brought bodies and laid them in our door-yards and along streets, he has done something very like it.”

In that and a thousand other ways, nothing would be the same after Antietam. 

Correction, Sept. 17, 2012: This article originally misspelled Mathew Brady’s first name. (Return.)

Robert M. Poole, former executive editor of National Geographic, is the author of On Hallowed Ground: The Story of Arlington National Cemetery.