American Battlefield Trust's map of the Battle of Middleburg
Maj. Gen. J.E.B. Stuart, screening Lee’s invasion route north toward Pennsylvania, sparred with Maj. Gen. Alfred Pleasonton’s Union cavalry. On the June 17, Col. Alfred Duffié’s isolated 1st Rhode Island Cavalry Regiment was attacked by the brigades of Thomas Munford and Beverly Robertson. The Rhode Island troopers were routed, taking heavy casualties. On June 19, J. Irvin Gregg’s cavalry brigade advanced, driving Stuart’s cavalry one mile west of town to Mount Defiance. Both sides were reinforced and mounted and dismounted skirmishing continued. Stuart was gradually pushed out of his position but fell back toward Upperville to a second ridge, still covering the approaches to the Blue Ridge Mountain gaps.