special order 191 was issued by robert e. lee in early september 1862. it was a handwritten order detailing lee's planned troop movements during his maryland campaign intended to win the american civil war. the document was recovered by union soldiers and passed on to major general george b. mcclellan. this was a piece of intelligence few battle commanders are ever lucky enough to receive. it gave the details of how lee had weakened his forces by splitting them up into several columns. it also laid out where each part of his army was to be at any given time. mcclellan, usually very slow to act, moved his forces more quickly this time. by the night of september 14, 1862, lee was no longer following his plan of attack. he was now reacting to mcclellan's troop movements. at this point lee's main problem became how to keep his army from being destroyed.