Northern fears of a continued offensive by Robert E. Lee were realized when he launched his Maryland Campaign on September 4, hoping to arouse pro-Southern sympathy in the slave state of Maryland.
Nordlig bekymring for en fortsat offensiv fra Robert E. Lee gik snart i opfyldelse, da han iværksatte sin Marylandkampagne den 4. september i håb om at vække sympatien for Sydstaterne i slavestaten Maryland.