And upon this act, sincerely believed to be an act of justice, warranted by the Constitution upon military necessity, I invoke the considerate judgement of mankind and the gracious favor of Almighty God. U. S. GOVERNMENT PRINTING OFFICE: 1986 0 - 157-109: QL 3 [Illustration: Maryland Seal] Antietam National Battlefield Maryland National Park Service U.S. Department of the Interior [Illustration: The Federal attack across Burnside Bridge, as portrayed (somewhat fancifully) in a postwar chromolithograph by Kurz & Allison. Library of Congress] The Bloodiest Day of the Civil War The Battle of Antietam (or Sharpsburg) on September 17, 1862, climaxed the first of Confederate Gen. Robert E. Lee’s two attempts to carry the war into the North. About 40,000 Southerners were pitted against the 87,000-man Federal Army of the Potomac under Gen. George B. McClellan. And when the fighting ended, the course of the American Civil War had been greatly altered. After his great victory at Manassas in August, Lee had marched his Army of Northern Virginia into Maryland, hoping to find vitally needed men and supplies. McClellan followed, first to Frederick (where through rare good fortune a copy of the Confederate battle plan, Lee’s Special Order No. 191, fell into his hands), then westward 12 miles to the passes of South Mountain. There on September 14, at Turner’s, Fox’s, and Crampton’s gaps, Lee tried to block the Federals. But because he had split his army to send troops under Gen. Thomas J. “Stonewall” Jackson to capture Harpers Ferry, Lee could only hope to delay the Northerners. McClellan forced his way through, and by the afternoon September 15 both armies had established new battlelines west and east of Antietam Creek near the town of Sharpsburg. When Jackson’s troops reached Sharpsburg on the 16th, Harpers Ferry having surrendered the day before, Lee consolidated his position along the low ridge that runs north and south of the town. [Illustration: “War is a dreadful thing.... Oh, my God, can’t this civil strife be brought to an end.” Clara Barton, who tended the wounded at Antietam during and after the battle.] The battle opened at dawn on the 17th when Union Gen. Joseph Hooker’s artillery began a murderous fire on Jackson’s men in the Miller cornfield north of town. “In the time I am writing,” Hooker reported, “every stalk of corn in the northern and greater part of the field was cut as closely as could have been done with a knife, and the slain lay in rows precisely as they had stood in their ranks a few moments before.” Hooker’s troops advanced, driving the Confederates before them, and Jackson reported that his men were “exposed for near an hour to a terrific storm of shell, canister, and musketry.”