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Maryland, Invasion of


MARYLAND, INVASION OF (September 1862). The defeat of Union General John Pope in the second Battle of Bull Run, and his retreat to the Washington, D.C., lines forced General Robert E. Lee to adopt a new plan of operations. He wrote Confederate President Jefferson Davis, "The present seems to be the most propitious time …to enter Maryland." Regardless of objections, Lee added, "We cannot afford to be idle." Aggressive movements, he thought, would insure the safety of Richmond, Virginia.

On 2 September 1862 marching orders were issued. Within a week troops were concentrating at Frederick, Maryland. Union General George B. McClellan, who had been restored to command, began organizing a force to defend Maryland. Meantime, Lee detached General Thomas J. ("Stonewall") Jackson to capture Harpers Ferry (in present-day West Virginia), while he led his army westward to an expected junction with Jackson in the vicinity of Hagerstown, Maryland. Once across South Mountain, Lee's line of supply would be through the Shenandoah Valley.

On 13 September McClellan reached Frederick. He hurried troops after Lee. Sharp fights took place at gaps in South Mountain; Lee sent reinforcements but by nightfall, finding the positions no longer tenable, he directed a retirement toward Sharpsburg, Maryland. McClellan advanced slowly, diverted by Jackson's movement against Harpers Ferry. As soon as that place surrendered, Jackson hurried to Sharpsburg, leaving A. P. Hill to dispose of captured property and prisoners and then follow promptly.

McClellan reached Sharpsburg on 16 September and spent the day testing Lee's line. His attacks the following day brought on the Battle of Antietam, characterized by more hard fighting than any other battle of the war. Lee, outnumbered, remained in possession of the field, but severe losses and heavy odds made it inadvisable to stay. McClellan did not attack again. On the night of 18 September Lee recrossed the Potomac "without loss or molestation," ending the campaign.


Johnson, R. U., and C. C. Buel, eds. Battles and Leaders of theCivil War. Vol. 2. Edison, N.J.: Book Sales, 1985.

McPherson, James M. Battle Cry of Freedom: The Civil War Era. New York: Oxford University Press, 1988.

Thomas RobsonHay/a. r.

See alsoAntietam, Battle of ; Bull Run, Second Battle of ; Civil War ; Fredericksburg, Battle of ; Harpers Ferry, Capture of .

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