The Battle of Monocacy Frederick County has a lot of history to it. Many major events in the history of the United States of America have taken place here. During the Civil War, many troops crossed through Frederick County. During one instance, there was a major battle, which many say saved Washington from being taken over by the Confederates. This battle took place just outside the city of Frederick. This battle was called the battle of the Monocacy. This battle was not very large, but extremely important. July 9, 1864 the Confederates, led by General Jubal Early, defeated the Union, led by General Lewis Wallace. When the Confederates crossed the Potom