Most people have never even heard of the battle of Guard Hill (aka Battle of Crooked Run) which occurred August 16, 1864 in the Shenandoah Valley near Front Royal, Virginia. According to James Harvey Kidd, it was an occasion that clearly illustrated George Armstrong Custer's military intuition. It certainly didn't turn out well for William T. Wofford's Georgians of Kershaw's division.
....We were just gathering around...to partake of a hastily prepared meal, when Fitzhugh Lee's cavalry, which had stealthily approached the ford, charged across and made a dash at our pickets. Major H. H. Vinton, of the Sixth Michigan was in command of of the picket line, and promptly rallying on his reserves, he courageously met Lee's attack and checked it. That dinner was never eaten. Custer's bugler sounded "to horse." And as if by magic, the men were in the saddle. Custer dashed out with his staff and ordered the Fifth Michigan forward, to be followed by the other regiments.
I supposed he would charge in the direction of the ford, where Fitzhugh Lee's cavalry was still contending with the Sixth Michigan. He did nothing of the kind. Moving diagonally to the left, he reached the crest overlooking the river just in time to surprise Kershaw [Wofford's brigade] in the act of crossing. The Fifth Michigan deployed into line in fine style and opened such a hot fire with their Spencers, that the head of Kershaw's column was completely crushed. Every Confederate who was across was either killed or captured. Many of those who were in the water were drowned and those on the other side were kept there. Just then, Devin's brigade came up, and helped to drive the cavalry across the river. The prisoners, all infantry numbered from three to five hundred.
[Source: James Harvey Kidd, Personal Recollections of a Cavalryman with Custer's Michigan Cavalry Brigade in the Civil War, Sentinel Printing Company, 1908, pp. 375-376.]
Jedediah Hotchkiss took the time to sketch the positions of the Confederate troops, but he would not have known the identity of the Federals.
The Tribune's special says: Col. DeVeirs [sic, Devin] who commands a brigade in Sheridan's cavalry, and who was wounded in an engagement at Front Royal on the 17th [sic, 16th] arrived here to-day. He brought with him two stands of rebel colors. Col. D. pronounces it one of the hardest fought battles of the war, and the first time during the history of the rebellion that cavalry defeated infantry. [Rutland Weekly Herald. (Rutland, VT), August 25, 1864, page 8.]
@Eric Wittenberg can you verify if this statement by Thomas C Devin is correct? Was Guard Hill/Crooked Run the first time that cavalry defeated infantry?