The First Battle of Bull Run, also known as the First Battle of Manassas, was the first major battle of the American Civil War. Fought on July 21, 1861, in Virginia near the town of Manassas, it involved Union and Confederate forces clashing in a fierce fight. The Confederate army, led by Generals Joseph E. Johnston and Thomas “Stonewall” Jackson, won the battle, surprising many who expected a quick Union victory. The battle showed that the war would be longer and more brutal than initially thought. It boosted Southern confidence and shocked the North.