The Battle of Brandy Station, also called the Battle of Fleetwood Hill, was the largest predominantly cavalry engagement of the American Civil War, as well as the largest to take place ever on American soil. It was fought at the beginning of the Gettysburg Campaign by the Union cavalry under Maj. Gen. Alfred Pleasonton against Maj. Gen. J.E.B. Stuart’s Confederate cavalry on June 9, 1863.
Union commander Pleasonton launched a surprise dawn attack on Stuart’s cavalry at Brandy Station. After an all-day fight in which fortunes changed repeatedly, the Federals retired without discovering Gen. Robert E. Lee’s infantry camped near Culpeper. This battle marked the end of the Confederate cavalry’s dominance in the East. From this point in the war, the Federal cavalry gained strength and confidence.
“Battle of Brandy Station.” Wikipedia