August 28, 1862 – Major General Thomas “Stonewall” Jackson’s Confederates attacked a portion of Major General John Pope’s Federal Army of Virginia northwest of Manassas, sparking a major battle.
By the 28th, Confederate General Robert E. Lee’s plan had been successful. One wing of his Army of Northern Virginia under Jackson had destroyed the Federal supply depot at Manassas Junction and positioned itself between Pope’s Federals and their capital at Washington. The other wing under Major General James Longstreet was hurrying through the Bull Run Mountains to join Jackson and give battle.
Pope’s Federals descended on Manassas Junction around 12 p.m. on the 28th, only to find that Jackson’s men had withdrawn from there during the night. This began a frustrating chase as Pope spent most of the day sending his troops in search of the elusive Confederates.
As Jackson moved west and Pope moved east and north, the two forces briefly clashed before the Confederates pulled back and disappeared into the woods. Federal Major General Irvin McDowell reported the enemy force as “some rear guard or cavalry party, with artillery.” The maneuvering on both sides resumed.
Meanwhile, Longstreet’s wing advanced to within 22 miles of Jackson’s position en route to linking with his force. Accompanying Longstreet, Lee received a message that morning stating that Jackson’s men had taken positions at Groveton, seven miles northwest of Manassas Junction, where they rested unnoticed by Federals.
As Jackson’s Confederates evaded Federal pursuers and assembled at Groveton, Pope received information that they had entered Centreville. One of Jackson’s divisions under General A.P. Hill had mistakenly marched there but the men retraced their steps to join Jackson’s main force at Groveton. Pope ordered his army to concentrate at Centreville, only to find the Confederates were gone. Pope’s exhausted troops marched and countermarched all day in the summer heat, often under confusing and contradictory orders.
To the west, Lee planned to rest his men so they could cross the mountains and join Jackson the next morning. But Confederates advancing to Thoroughfare Gap between the mountains found their path blocked by General John Buford’s Federal cavalry. They drove the cavalry off, but then General James B. Ricketts’s Federal division arrived and opened artillery fire. A severe fight ensued as the Confederates tried turning the enemy right. The Federals finally withdrew after dark, allowing the Confederates to pass through the gap in one of the more remarkable operations in northern Virginia.
By mid-afternoon, Jackson had positioned his men in the woods along Stony Ridge and an incomplete railroad embankment north of the Warrenton Turnpike to Centreville. Confederates under Lee and Longstreet could easily reach Jackson after moving through Thoroughfare Gap. Jackson received a message from Lee around 3 p.m. stating that Longstreet would arrive sometime the next day.
Jackson’s men rested for about five hours before General Rufus King’s division of McDowell’s corps unknowingly crossed their hidden front along the Warrenton Turnpike to join the main army. Jackson, hoping to coax Pope into moving in his direction, ordered his men to attack.
When it seemed the Confederates would gain an easy victory, they met unexpected resistance from Brigadier General John Gibbon’s Black Hat Brigade of westerners near Brawner’s Farm. Fierce combat ensued; General William Taliaferro, one of Jackson’s division commanders, later recalled that “there was very little maneuvering and very little tactics… it was a question of endurance–and both endured.”
Both sides sustained heavy casualties before the fighting ended at nightfall. The Federals lost about 1,110 of the 2,800 men engaged, with the Black Hat Brigade taking 751 of those losses. Their ferocity earned them the nickname the “Iron Brigade.” A soldier later wrote that the brigade was always ready for combat, but after this battle at Groveton, “we were never again eager.”
Jackson lost about 1,300; Brigadier General Isaac R. Trimble an