Civil War Daily Gazette

A Day-By-Day Accounting of the Conflict, 150 Years Later

Antietam – The Most Terrible Battle of the Age

September 17, 1862 (Wednesday)

“We are in the midst of the most terrible battle of the age,” wrote General George McClellan to his wife in the early afternoon. McClellan, who had come to be known as grossly inaccurate when it came to estimations of pretty much everything, was dead on. Before the battle of Sharpsburg, along the winding Antietam Creek was even half over, it was the most terrible battle of the war.

“So far God has given us success but with many variations during the day,” he continued, back to his less-than-accurate accounts.

By the time McClellan wrote his wife and to Washington, giving more or less the same story, the morning battles had ended with anything but a full success. Hooker’s First Corps had attacked Stonewall Jackson’s troops from the North Woods through The Cornfield and East Woods. But, even with the addition of Mansfield’s Twelfth Corps, they could not hold the ground they took. The objective had been the ground around The Dunkard Church, which, if captured, would turn General Lee’s flank. Some of Mansfield’s men reached it, driving off Rebel batteries in the assault, but soon they were beaten back like their brethren.

General Hooker, while trying to rally his men, was wounded and left the field. His corps went to George Meade, but the field command was left to nobody. Another corps, the Second, was added to the confusion to little effect, except for one division that stumbled upon Confederates in The Sunken Road, opening a new phase of the battle.

For nearly four hours, the quarter-mile stretch of farm road was held, taken, retaken, charged and counter-charged by both sides. By the time McClellan was writing the short letter to his wife, his men were scaling parapets of their dead comrades to capture what quickly became known as Bloody Lane.

If this was the “success” McClellan has written about, he did nothing to take advantage of it. The Rebels were forced from their position, leaving Lee’s army ready to be sliced in two. McClellan did nothing. He had troops upon troops standing, waiting, and threw none forward to end it.

In Washington, where General-in-Chief Henry Halleck received McClellan’s optimistic dispatch, things were surprisingly calm. But calm did not lend itself to clarity. McClellan had sent few messages over the past couple of days, and rumors of Harpers Ferry and of the Army of the Potomac were rampant. With the Rebel army north of the city, a victory over McClellan could mean an invasion of Pennsylvania or the taking of Baltimore or even Washington itself.

The calm, at least for Henry Halleck, came from the reports that Lee’s army had slipped back into Virginia. Because of McClellan’s lack of communication, he knew nothing of even the chance of a battle until he received word in the middle of it from McClellan himself.

The attacks from the north, through The Cornfield, had prompted McClellan to change his tactics. Since Lee was strongest in the north, he must be weakest in the south. Already poised for an attack was the Ninth Corps under Ambrose Burnside and Jacob Cox. He ordered them forward to create a division, hoping to draw Confederates away from the main attack.

Burnside, with 12,000 men, waited. His orders arrived around 10am. Prior to that, three divisions of Rebels waited for him, ready to contest his crossing of the small Rohrbach’s Bridge that would shortly bear his name. But as the fighting drew heavy to the north, General Lee wicked men from wherever he could find them. Two Rebel divisions left Burnside’s front, and then most of another, leaving a mind-bogglingly scant 400 Georgians to defend the crossing.

Spending hours trying to figure out how to cross, and looking for a passable ford even farther south, Burnside whiled away the late morning. McClellan had sent couriers to find out what was keeping him, but none could offer a logical reason for the waiting.

The first attack was little more than a probe and easily beaten back. The second attack was meant for a brigade to storm down towards the bridge and rush it. The troops, however, got lost and stumbled their way towards the creek, missing the bridge by 350 yards. There they stayed, acting as pickets and skirmishers.

Before the first attack failed, Burnside sent a division south, in hopes of crossing a ford to get behind the Georgians. By this time, it was quite obvious that they were lost, too.

To cross the Rohrbach’s Bridge, a front of only eight men could be presented to the Rebels, who were perched well above the bridge and able to pick off Yankees with little danger to themselves. The next attempt would take a different approach, using the road leading to the bridge. Nobody could get lost, and if they hurried, casualties might not be so bad. But they were. The road ran parallel to the creek and the men were mowed down.

In a final attempt, the 51st Pennsylvania and 51st New York were charged down a hill, across the road to the bridge and across. They had apparently been promised whiskey by their teetotaling commander, and that was enough to make them fight.

The bridge fell and the Georgians retreated. The south end of the field was in Federal hands. But Burnside, though prodded by McClellan to move, did not. He had somehow forgotten to resupply his men with ammunition.

The Federal crossing barely phased General Lee, who knew that A.P. Hill’s Division would soon arrive from Harpers Ferry. Neither McClellan nor Burnside had any idea that another fresh Rebel division even existed. Burnside’s plan, once he was able to construct one, was to work around the very weak right flank of the enemy. This, he believed, would cut them off from Boteler’s Ford, their only means of retreating back across the Potomac.

At first, he did quite well, pitting his 8,500 men against no more than 2,800 Rebels, who put up a vicious defense. But, after repeated assaults, the line broke and the Rebel flank began to crumble. Through the streets of Sharpsburg, the Rebels ran in terror as General Lee did what he could to stem the tide of his disintegrating flank.

Only one small brigade remained, but looking towards the road leading to Harpers Ferry, Lee could see dust. It was A.P. Hill’s Division. Lee ordered whatever artillery he could find to focus everything it had upon the Yankees attacking his right flank, hoping to hold out for just a few minutes more.

When Hill’s Division arrived, around 3:30pm, their commander threw them into the fray in piecemeal fashion. He didn’t bother to properly align them or dress them as if on parade. Within ten minutes, the first of them were killing and dying. The impromptu and advantageous flank attack was enough to confound the Federal push. Hill’s men drove Burnside’s troops back to their bridgehead at the Antietam.

Burnside called upon McClellan for reinforcement, but McClellan lied, telling him that he had no infantry left. In truth, he had two full corps – the Fifth and Sixth. When Burnside’s plea arrived, McClellan turned to General Porter, commanding the Fifth Corps. Porter merely shook his head and any notion of saving Burnside was gone. The battle was all but over.

The battle of Antietam was, and still remains, the bloodiest day in American history. The Union sustained 2,108 dead, 9,540 wounded and 753 missing. This was 25% of those who fought. The Rebels lost around 1,546 dead, 7,752 wounded, 1,108 missing, or 31% of the troops engaged.

Still, with the losses, General Lee had no plans to retreat. He shifted some artillery, condensed his lines here and there, but, holding most of the ground he held twenty-four hours previous, he would not yet be moved.1



  1. To write about a battle such as this in a mere 1,400 words is impossible. There are, necessarily, omissions, mistakes, and abbreviations. Hundreds of pages could be written on the things to which was given here only a passing notice. And to those books, you should turn. Properly writing this post, for me, is an impossible task. Still, here are the sources I used to cobble this thing together: Landscape Turned Red by Stephen W. Sears; The Civil War Papers of George B. McClellan; Stonewall Jackson by James I Robertson; George B. McClellan by Stephen W. Sears; The Diary of Gideon Welles; and a few pages from the Official Records, Series 1, Vol. 19, Part 2. []
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4 Responses

  1. Mary McClure says

    I just found this site. Antietam has fixed feelings for me. I am originally from Maryland and was born on the anniversary of the Battle of Antietam.. My great grandfather was wouned at the battle; but he recovered to rejoin the Maryland Union forces. Not many people realize that the State of Maryland put up a round monument there to honor all Maryland soldiers that found there – the upper half dedicated to the North and the bottom half to the South. Another reason for it being called the “Old Line State” even though President Lincoln had the Maryland legislaturers imprisioned at Fort McHenry.

  2. Kenneth Kellogg says

    McClellan was still convinced that Lee had over 100,000 men. (In reality, he didn’t have half that number.) When McClellan was considering sending in V Corps, corps commander Fitz John Porter is reported to have replied, “Remember, General, I command the last reserve of the last Army of the Republic.” Those were the very words to make the ever-cautious McClellan hesitate.

    • Ryan Beggar says

      Thanks! I guess given that assumption it’s less baffling.

  3. Ryan Beggar says

    So, why did McClellan refuse to commit the Fifth and Sixth? Was it simply that he believed it pointless? It seems baffling to me that he’d allow Burnside to fight without reinforcement…

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