Part of the plan for the Army of Northern Virginia’s invasion of Maryland was to “liberate” the state from Lincoln’s holding it in the union by force. And Robert E Lee also hoped to get new recruits joining his army which was decimated from the 7 Days battles and 2d Manassas. Unfortunately, he invaded the wrong half of the state as the eastern half was more southern leaning then the western half. Gary Gallagher in his book “Lee and His Generals in War and Memory” discusses this salient fact.
Lee’s expectation of gathering recruits in Maryland came to little. Indeed, illusions about pro-Confederate Marylanders waiting to break free of Union oppression disappeared even before the battle of Antietam. As early as September 7, Lee had cautioned Davis that despite “individual expressions of kindness that have been given,” he did not “anticipate any general rising of the people in our behalf.” The next day, September 8, Lee issued a proclamation informing Marylanders that “our army has come among you, and is prepared to assist you with the power of its arms in regaining the rights of which you have been despoiled.”
The numerous Germans in western Maryland turned a distinctly cold shoulder to the intruders. The ragged clothing and gaunt frames of the Confederates, as well as their lice and pungent odor, put off even sympathetic civilians. No more than a few hundred Marylanders stepped forward to join the thin ranks of the Army of Northern Virginia.
Illustration from Harper’s Weekly September 27, 1862