This thesis examined the movements of Rufus King's Federal division during a portion of the Second Manassas Campaign. With an emphasis on the role of John Gibbon's brigade, this study concentrated on the battle fought on the evening of August 28, 1862 near Groveton, Virginia between King's division and two Confederate divisions under Stonewall Jackson. Events leading up to file battle, poor cooperation between the Union generals and the faulty deployment by Jackson were stressed, as was the severity of the fighting.The withdrawal of King's division following the battle was portrayed as an important strategic error which allowed the two wings of the Confederate army to unite the following day. Although the Union troops fought Jackson's larger force to a draw, poor leadership by the Union generals resulted in tide loss of the advantages gained by the fighting. The Battle at Brawner Farm was an important event in the campaign, although it has generally been overlooked by historians.