Lost Order

Special Order 191 (series 1862) (the "Lost Dispatch," and the "Lost Order") was a general movement order issued by Confederate Army General Robert E. Lee on about September 9, 1862 during the Maryland Campaign of the American Civil War. A lost copy of this order was recovered in Frederick County, Maryland, by Union Army troops, and the subsequent military intelligence gained by the Union played an important role in the Battle of South Mountain and Battle of Antietam.

The order was drafted on or about September 9, 1862, during the Maryland Campaign. It gave details of the movements of the Army of Northern Virginia during the early days of its invasion of Maryland. Lee divided his army, which he planned to regroup later: according to the precise text Maj. Gen. Stonewall Jackson was to move his command to Martinsburg while McLaws's command and Walker's command "endeavored to capture Harpers Ferry." Maj. Gen. James Longstreet was to move his command northward to Boonsborough. D. H. Hill's division was to act as rear guard on the march from Frederick.

Lee delineated the routes and roads to be taken and the timing for the investment of Harpers Ferry. Adjutant Robert H. Chilton penned copies of the letter and endorsed them in Lee's name. Staff officers distributed the copies to various Confederate generals. Jackson in turn copied the document for one of his subordinates, Maj. Gen. D. H. Hill, who was to exercise independent command as the rear guard. Hill said the only copy he received was the one from Jackson.

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