American Civil War Monocacy National Battlefield in Frederick County interprets the American Civil War battle that was fought on July 9, 1864, known as "The Battle That Saved Washington." This is one of the last battles that the Confederates would carry out in Union territory. During the Civil War, Frederick was fiercely contested ground with numerous skirmishes and exhaustive troop movements accompanying the nearby battles of Antietam, Gettysburg, South Mountain and Monocacy. 2012 is the 150 Commemoration of the Maryland Campaign. Subject Matter: Monocacy National Battlefiled, American Civil War, historic sites, Maryland Campaign, Sesquicentennial, Civil War 150, Frederick County tourism, Maryland