This printed map by the Office of the Chief Engineer of the War Department details the fighting at the Battle of Bull Run on July 21, 1861. Named for the creek or “run” in northern Virginia along which the fighting took place, Bull Run was the first major battle of the American Civil War. After halting several attacks ordered by Union commander General Irvin McDowell, the Confederates under General Pierre Beauregard launched a successful counterattack that drove the tired and inexperienced Union forces back toward Washington. The failure of the Union Army to win a victory at Bull Run signaled the onset of a long and costly war. In a conflict that lasted just over four years, approximately 620,000 American soldiers died, around 360,000 on the Union side, and around 260,000 on the Confederate side. The chief results of the war were the abolition of slavery and the preservation of the United States as a union.