Battle of Sharpsburg (Antietam) 17 September 1862

I've blogged on this subject before, and this post appeared, slightly differently, a couple of years ago. But the Battle of Sharpsburg is both on my mind, and part of my current reading, so the post seems as timely to me now, as then.

Headquarters, Alexandria & Leesburg Road

Near Dranesville

September 3, 1862

Mr. President:
The present seems to be the most propitious time since the commencement of the war for the Confederate Army to enter Maryland. The two grand armies of the United States that have been operating in Virginia, though now united, are much weakened and demoralized. Their new levies of which I understand sixty thousand men have already been posted in Washington, are not yet organized, and will take some time to prepare for the field…

The army is not properly equipped for an invasion of an enemy’s territory. It lacks much of the material of war, is feeble in transportation, the animals being much reduced, and the men are poorly provided with clothes and in thousands of instances are destitute of shoes. Still, we cannot afford to be idle, and though weaker than our opponents in men and in military equipments, must endeavor to harass, if we cannot destroy them. I am aware the movement is attended with much risk. . .

If the Quartermaster Department can furnish any shoes, it would be the greatest relief. We have entered upon September, and the nights are becoming cool. . .

R.E. Lee

Genl

General Robert E. Lee to President Jefferson Davis, 3 September 1862 (from Dowdey, Manarin, The Wartime Papers of Robert E. Lee, Da Capo 1961, p. 294).

Headquarters, Near Fredricktown, Maryland

          September 8, 1862

Mr. President:

The present posture of affairs, in my opinion, places it in the power of the Government of the Confederate States to propose with propriety to that of the United States the recognition of our independence. . .

R.E. Lee                                                                                                                 

         Genl Comdg.

Lee to Davis, (Papers, at p. 301).

Today is the 151st anniversary of the Battle of Sharpsburg, known in the north as Antietam, the bloodiest day of battle on the North American continent. No American armies ever assembled contended for such high stakes as their brothers who fought and died this day near the Maryland town of Sharpsburg, hard by Antietam Creek, on this day, so many years ago.

Overshadowed in the popular imagination by Gettysburg, Sharpsburg, a tactical draw, but strategically, a defeat for the South, deprived the fledgling Confederate States of its best possibility of military victory. After Sharpsburg, foreign diplomatic recognition and help for the South’s struggle for independence was exceedingly unlikely.

Southern morale was sky-high in the summer of 1862, at least in the east. After a series of disasters following First Manassas, in the winter of 1861-62, the Confederacy found itself some generals. Robert E. Lee saved the Confederacy’s capital at Richmond, Virginia from a much larger US force under the talented, but slow, George B. McClellan. Meanwhile, in the Shenandoah valley, the tiny Valley Army, under Thomas J. “Stonewall” Jackson, beat the Yankees again and again, and briefly threatened Washington, or so the hard-pressed Lincoln administration thought.

Following McClellan’s reverses near Richmond, Confederate armies passed to the offensive all across the south. Lee moved from the Richmond area back towards Washington. From 28-30 August 1862, Lee’s Army of Northern Virginia won its greatest victory at Second Manassas. Meanwhile, in the west, Braxton Bragg’s hard-luck Army of Tennessee moved into Kentucky, threatening to make the Bluegrass State’s nominal status as a Confederate state a reality.

Defeat at the very gates of Washington, and Bragg's invasion of Kentucky shocked and embarrassed the Lincoln administration. The federal government’s policy of forcing the Southern states at gunpoint back into the Union they wanted to leave teetered on the brink of ruin. In Britain, William Gladstone, chancellor of the exchequer, told a Newcastle audience that southerners had “made a nation.” In Paris, the Confederacy’s strongest foreign friend, Emperor Napoléon III, told his foreign ministry to open quiet talks with England on joint diplomatic recognition of the Confederacy. For once, both diplomatic and military momentum seemed to be moving in favor of the South.

Under these circumstances, Lee’s decision to move north was a no-brainer, particularly given the General’s knowledge, which jumps out of his papers and correspondence, of the South’s dismal long term military prospects. Lee fully recognized the superiority of his enemies in “numbers, resources, and all the means and appliances for carrying on the war” and warned his President that “we have no right to look for exemptions from the military consequences of a vigorous use of these advantages.” Moving north and beating the enemy on his own soil raised the odds of foreign support, boosted Southern morale, while damaging the enemy's; relieving the Southern home front from the pressure of invading enemy armies, and giving Northern civilians a small taste of what their armies dished-out all over the South.

Still, the campaign was, as Lee and his President knew, a giant gamble. During the first days of September, as the tough Confederate infantry moved down the roads of northern Virginia, across the Potomac and into US territory, problems were readily apparent. Southern industry was simply not up to properly equipping the army. Lee’s force was in part shoeless, clad in rags with only coincidental resemblance to uniforms, largely armed and equipped with enemy weapons and supplies scavenged from the victorious battlefields of that summer. (Lee’s correspondence during this period shows a preoccupation with guarding the site of the Manassas victory, and hauling away the huge quantities of abandoned Yankee supplies and arms).

Also, the army was organizationally cumbersome: no formal Corps structure yet existed; its over-large divisions informally divided into two wings too large for the wing commanders, Longstreet and Jackson, to really handle. Still, in the annals of American war, finer troops never bore arms, and in Lee, Longstreet, Jackson, Jeb Stuart, the Hills, Hood, Early, and legions of others, the Confederates had a splendid band of commanders.

The amazing run of victories that summer produced another problem: continuously marching and fighting since March, the army was completely exhausted, and in need of a spell in camp to rest, re-equip and absorb replacements. Replacements, that is, such as there were. Unlike its bigger, richer foe, the Confederate States was already scraping the bottom of its manpower barrel, which further explains Lee’s determination to try to end the war quickly. But General Lee was pushing his force to its physical limit. The long marches (think of barefoot or ill-shod troops and horses on the macadam and gravel roads found north of the Potomac); combined with utter exhaustion and poor supplies produced rampant straggling. Lee’s army, already seriously under-strength, numbered no more that 55,000, and he could not assemble more than 45,000 for the Battle of Sharpsburg.

The campaign began well enough. With the main northern armies camped around Washington, Lee moved into central Maryland, around Frederick. A glance at the maps and Lee's dispatches indicates that his plan seems to have been much the same as he used in the Gettysburg campaign the next year: a move into Pennsylvania, so as to draw the US Army round Washington after him, and then defeat it in detail, as it came up, somewhere between Harrisburg and Gettysburg. . .

However, the Yankees left a huge garrison at Harper’s Ferry, Virginia, isolated and vulnerable, and Lee sent Stonewall Jackson to pounce on it. The US garrison there surrendered on 15 September – almost 12,000 troops going into Southern captivity. This was the largest mass surrender of a US Army until 1942.

To close the trap around Harper’s Ferry, Lee had to divide his already outnumbered army. Under pressure from politicians and newspapers, the US Army of the Potomac moved out of Washington, in typical slow McClellan fashion, after Lee. The weak point of the Confederate military machine was administration, and this now came into play. In a field near Frederick, Maryland, (former campground of a CS Infantry Division), Private Barton W. Mitchell, 27th Indiana Volunteer Infantry, found a piece of paper wrapped around some cigars. The paper, a Confederate military dispatch, “Special Orders No. 191,” gave McClellan his opportunity: “I now know all the plans of the rebels,” McClellan complacently telegraphed Washington.

The “Lost Order,” one of the most consequential pieces of paper in American history, told McClellan exactly where all of Lee’s units were, spelled out their composition, and gave hints as to future operations. Best of all for the North, Lee was completely ignorant of the fact that his enemies now knew his plans.

McClellan told a subordinate: "Here is a paper with which, if I cannot whip Bobby Lee, I will be willing to go home" and, indeed, Napoléon probably could have won the whole war on the strength of that information. Lee had only 19,000 men immediately available to set against McClellan’s 87,000 because Stonewall Jackson was still finishing with Harper’s Ferry. Fortunately for the Confederates, McClellan, (as usual, beguiled by other false intelligence giving Lee three times his actual strength), moved slowly. However, McClellan was able to force Lee to battle in front of the town of Sharpsburg, along Antietam Creek, on unfavorable ground, his back against the Potomac River, and with his army incompletely concentrated.

McClellan’s dithering delayed the battle for a full day, giving Jackson time to arrive with most of his troops from Harper’s Ferry. Still, when the battle began, at dawn on the morning of 17 September, Lee, who had managed to assemble about 35,000 troops, was outnumbered by over two to one.

Sharpsburg was really several separate battles, because McClellan was unable to get his army to make one, all out, coordinated attack. Had he been able to do so, Lee’s army would most probably have been completely destroyed. Instead, the different corps of the Union army attacked, more or less in sequence, separately, from the north end of the field to the south. McClellan never engaged more than two of his six corps at a time, and some of his units never got into action at all. The Confederates, better commanded, used all of their troops.

The slaughter defies description. 8,000 men were killed or wounded in the initial dawn attack alone. With rivers on both flanks of the battlefield, Sharpsburg was fought out as a series of bloody frontal assaults at places called “the Cornfield,” “Bloody Lane,” “Burnside’s Bridge,” the “West Woods.” Fighting was hand-to-hand at many places. The Cornfield changed hands fifteen times that day.

Several times, the Union troops were on the verge of breaking through the Confederate lines, but each time were repulsed short of their objectives, with horrific casualties on both sides. "Where is your division?" John Bell Hood was asked. "Dead in the Cornfield," his reply. "Lee's army was ruined," the Confederate artilleryman E. Porter Alexander later wrote, "and the end of the Confederacy was in sight." But somehow, the embattled, outnumbered Confederates held on, even counterattacking in places. However, by midday, the Confederates were on the ropes, exhausted, last reserves expended, generals and division staffs taking their places in the firing line. McClellan, fatally, hesitated, refraining from committing his last reserves, which would have shattered Lee's stricken center. To the soldiers, it seemed as if night would never come.

The battle ended in the early evening, about 5:30 p.m., with a last US effort to turn the Confederate right flank at Burnside’s Bridge. For the only time during this long battle, observers noted Lee showing signs of real anxiety, anxiously looking southwest, towards Harpers Ferry, for his last division, A.P. Hill's, en route from that place. Fortunately for the Southerners, Hill's troops arrived in the nick of time. The armies eyed each other warily all during the next day, but fighting did not resume, and the Battle of Sharpsburg ended.

Although the battle was a tactical draw, it was a strategic defeat for the South, because McClellan’s disjointed, uncoordinated attacks had hurt Lee’s army bad enough to force him to withdraw during the night of 18 September. The Southern retreat south of the Potomac completely overshadowed the mass surrender at Harper’s Ferry, and possibly prevented foreign diplomatic recognition of the Confederacy.

Despite this, the stand at Sharpsburg of Robert E. Lee’s greatly outnumbered Army of Northern Virginia was probably the Confederate Army’s finest hour. 2,100 US soldiers, and 1,500 CS soldiers died that day a one-day death toll by hostile action not rivaled in America till 9/11. Adding wounded, missing and prisoners on both sides, casualties totaled nearly 25,000. The Civil War was not decided at Sharpsburg – the fall of Atlanta, two years later, did that. But the last chance of the South to outright win the war, as opposed to surviving an attritional struggle, died at Sharpsburg.