First Battle of Bull Run (First Manassas): The Wake-Up Call for Both Sides in the American Civil War

The First Battle of Bull Run (First Manassas) on 21 July 1861 was the first major battle of the American Civil War and a wake-up call for both sides which, until then, believed that the war would be over quickly, and they would come out the winner. Each side pointed to earlier, smaller, battles to support their claim.