Brockenbrough assumed command of the brigade after Field was wounded at the Second Battle of Bull Run and led it two days later at Chantilly.

During the Maryland Campaign, Brockenbrough took part in the capture of Harpers Ferry, and then marched with the rest of the Light Division to the rescue of Gen. Robert E. Lee's army at Sharpsburg; his brigade was deployed on the far right of A.P.

At Fredericksburg, his brigade was ordered to plug a hole in the Confederate line that was being exploited by Union troops under Maj. Gen. George G. Meade.

At the Battle of Gettysburg, Brockenbrough's brigade was in the rear of Heth's column during the march on the Chambersburg Pike, July 1, 1863, and thus missed the morning attacks against the Union cavalry and the I Corps.

There is no record that Brockenbrough marched with his men toward Cemetery Ridge that day, however, and Col. Robert M. Mayo of the 47th Virginia Infantry was in temporary command.

During the Confederate retreat back to Virginia, Brockenbrough attempted to reclaim some of his damaged reputation by making a reckless advance against Union troops at Falling Waters on July 14, suffering numerous casualties.

Gen. Henry Harrison Walker, was given command of the brigade, returning Brockenbrough to the 40th Virginia, which he led at Bristoe and Mine Run.