Most authors of the Maryland Campaign brush past South Mountain in a few paragraphs or a single chapter. Jordan, however, presents a full-length study based upon extensive archival research, newspaper accounts, regimental histories, official records, postwar reunion materials, public addresses, letters, and diaries.
Many readers of Civil War history have been led to believe that the battle of South Mountain (September 14, 1862) was but a trifling skirmish, a preliminary engagement of little strategic or tactical consequence overshadowed by Antietams horrific carnage just three days later. In fact, the fight was a decisive Federal victory and important turning point in the campaign, as historian Brian Matthew Jordan convincingly argues in his fresh interpretation Unholy Sabbath: The Battle of South Mountain in History and Memory, September 14, 1862.