Northern Virginia Campaign

• Major General Thomas J. JacksonCedar Mountain, Rappahannock Station, Manassas Station Operations, Manassas, Second, Chantilly
• Lieutenant General James LongstreetThoroughfare Gap
• General Robert E. LeeManassas, Second

• Major General Nathaniel P. BanksCedar Mountain
• Major General John PopeRappahannock Station, Manassas, Second
• Brigadier General G.W. TaylorManassas Station Operations
• Brigadier General James RickettsThoroughfare Gap
• Major General Philip KearnyChantilly
• Major General Isaac StevensChantilly

Opposing forces

No information about the Union forces appears in the source for this section.

Initial movements

On July 26, Lee sat down with Capt. John S. Mosby, the cavalry officer and partisan raider who had just been released from Union captivity. While passing through Hampton Roads as a prisoner, Mosby had noticed unusual activity among naval transports and concluded that Maj. Gen. Ambrose Burnside's men, veterans of the fighting in North Carolina, were on their way to bolster Pope's ranks. Determined not to let those reinforcements settle into place, Lee acted the very next day, sending Maj. Gen. A.P. Hill with 12,000 troops to link up with Jackson, all while keeping McClellan occupied through artillery fire and feigned maneuvers meant to mislead him.

Meanwhile, McClellan pushed a force forward from Harrison's Landing toward Malvern Hill, prompting Lee to march south and counter the move, though McClellan ultimately pulled his troops back. Convinced despite this that his army faced overwhelming numbers, McClellan informed Washington that any renewed push toward Richmond would require at least 50,000 additional soldiers.

By August 3, General-in-Chief Henry W. Halleck had ordered McClellan to abandon the Peninsula entirely and bring his forces north to assist Pope. McClellan objected to the order and delayed his withdrawal until August 14. When the Army of the Potomac finally departed, nearly all of it returned to Washington, with only a single division of the IV Corps remaining behind on the Virginia Peninsula.

Confederate

On July 29, Pope shifted his command post from Washington out to the field itself. Halleck had briefed him on the intended union with McClellan's force, yet instead of holding back for that to unfold, Pope pushed a portion of his troops toward Cedar Mountain, positioning them to send cavalry on raids against Gordonsville. Jackson, for his part, pressed forward to Culpeper Court House on August 7, seeking a chance to strike one of Pope's corps before the remainder of the army could join together.

Aftermath

Both armies paid a steep price for the fighting in northern Virginia, though Lee managed his smaller force more economically. Out of roughly 75,000 men engaged, Union losses reached 16,054, including 1,724 killed, 8,372 wounded, and 5,958 missing or captured, a toll similar to what had been suffered in the Seven Days Battles two months prior. Confederate casualties totaled 9,197 out of 48,500 engaged, with 1,481 killed, 7,627 wounded, and 89 missing or captured.

Edward Porter Alexander later observed that the Army of Northern Virginia gained a morale so magnificent it made the men fight as though they numbered twice as many, a spirit they retained all the way to the surrender at Appomattox. He noted that Lee's faith in his soldiers and their faith in him were so evenly matched that no one could say which ran deeper.

For Lee and his two chief lieutenants, the campaign stood as a resounding success. The historian John J. Hennessy called it Lee's finest campaign, calling it the point where strategy and tactics came together most happily for him. He mixed daring moves with sound restraint, and he assigned his subordinates to the tasks that suited them best. Jackson's flanking march, covering 54 miles in just 36 hours to reach the Union army's rear, was, in Hennessy's words, the boldest maneuver of its kind seen in the war, one Jackson carried out without flaw. Longstreet's assault on August 30 came in with such timing, force, and speed that it came nearer to wrecking a Union army than almost any other attack of the conflict.

Pope, having been outmaneuvered by Lee, found himself nearly under siege in Washington. Only his personal and political closeness to Lincoln spared his career from ruin. He was sent instead to Milwaukee, Wisconsin, to lead the Army's Department of the Northwest, where he later fought in the Dakota War of 1862. Command of the Union forces defending Washington fell to Maj. Gen. George B. McClellan, whose Army of the Potomac absorbed the Army of Virginia when that force was dissolved on September 12, 1862.

With Pope removed as a threat and McClellan busy reorganizing his troops, Lee moved his army northward on September 4, crossing the Potomac into Maryland. This move opened the Maryland campaign, leading to the battles of Harpers Ferry, South Mountain, and Antietam.

Today the National Park Service maintains the Bull Run battlefields as part of Manassas National Battlefield Park.