The Northern Virginia Campaign, also known as the Second Bull Run Campaign or Second Manassas Campaign, is a series of battles fought in Virginia during August and September 1862 in the Eastern Theater of the American Civil War.

Confederate General Robert E. Lee followa up his successes of the Seven Days Battles in the Peninsula Campaign by moving north toward Washington, D.C., and defeating Maj. Gen. John Pope and his Army of Virginia.

Concerned that Pope's army will combine forces with Maj. Gen. George B. McClellan's Army of the Potomac and overwhelm him, Lee sends Maj. Gen. Thomas J. "Stonewall" Jackson north to intercept Pope's advance toward Gordonsville.

The two forces initially clash at Cedar Mountain on August 9, a Confederate victory.

Lee determines that McClellan's army on the Virginia Peninsula is no longer a threat to Richmond and sends most of the rest of his army, Maj. Gen. James Longstreet's command, following Jackson

Jackson conducts a wide-ranging maneuver around Pope's right flank, seizing the large supply depot in Pope's rear, at Manassas Junction, placing his force between Pope and Washington, D.C.

Moving to a very defensible position near the battleground of the 1861 First Battle of Bull Run (First Manassas), Jackson successfully repulses Union assaults on August 29 as Lee and Longstreet's command arrive on the battlefield.

On August 30, Pope attacks again, but is surprised to be caught between attacks by Longstreet and Jackson, and is forced to withdraw with heavy losses.

The campaign concludes with another flanking maneuver by Jackson, which Pope engages at the Battle of Chantilly on September 1.

Lee's maneuvering of the Army of Northern Virginia against Pope is considered a military masterpiece.