The First Battle of Bull Run

(LoC) On July 21, 1861, a dry summer Sunday, Union and Confederate troops clashed outside Manassas, Virginia, in the first major engagement of the Civil War, the First Battle of Bull Run.
Union General Irvin McDowell hoped to march his men across a small stream called Bull Run in the vicinity of Manassas, Virginia, which was well-guarded by a force of Confederates under General P. G. T. Beauregard. McDowell needed to find a way across the stream and through the Southern line that stretched for over six miles along the banks of Bull Run.
McDowell launched a small diversionary attack at the Stone Bridge while marching the bulk of his force north around the Confederates' left flank. The march was slow, but McDowell's army crossed the stream near Sudley Church and began to march south behind the Confederate line. Some of Beauregard's troops, recognizing that the attack at Stone Bridge was just a diversion, fell back just in time to meet McDowell's oncoming force. Continued