During the Civil War of the United States, the Union Army of the North and the Confederate Army of the South met for the second time at Bull Run in Manassas, Virginia. The Second Battle of Bull Run took place on 28-30 August 1862 and was a pivotal battle in a longstanding offensive waged by Confederate General Robert E. Lee's army.
The Second Battle of Bull Run was preceded by strategic Union Army movements. Union Major General John Pope moved his troops south toward Gordonsville to both protect Washington and the Shenandoah Valley, and to draw Confederate troops away from another battle farther away, in which the Union Army was suffering badly. Because Confederate General Stonewall Jackson had captured Manassas, Pope's line of communication with Washington was cut off.
Pope was on the defensive, but he was unaware of the numbers of Confederate soldiers General Lee had committed to the battle. Lee had withdrawn many of his troops from another battle that he considered inconsequential, and he committed them to Manassas. With Pope unaware of the number of troops he was up against, the Second Battle of Bull Run was poised to begin.
Pope's troops battled Stonewall Jackson's troops early in the Second Battle of Bull Run, which resulted in something of a stalemate. But Pope was convinced he had the upper hand, and he launched an offensive against Jackson's troops. These attacks were unsuccessful, and casualties on both sides piled up quickly.
What Pope did not know was that at another location on the battlefield, a Confederate force led by Confederate General James Longstreet had broken through a flank of the Union Army to join the rest of Lee's Confederate troops. Pope redoubled his offensive efforts, unaware that additional Confederate troops had joined the Second Battle of Bull Run.
When Pope sent the next wave of soldiers in on the attack, Confederate artillery all but decimated the Union flank. Confederate General Longstreet counterattacked, and the Union flank fully faltered. The Union Army was forced to retreat, bringing the battle to a close.
The Second Battle of Bull Run was a much larger battle than that of the First Battle of Bull Run, which took place on the same battlefield a year earlier. The Union Army suffered more than three times as many casualties than they did in the first battle, and General Pope was relieved of his command shortly after his defeat.