The Battle of Chantilly was a fierce fight during a violent thunderstorm, on September 1st, 1862, during the American Civil War between Jackson's division of Robert E Lee's army and portions of Joseph Hooker's, Jesse Reno's, McDowell's and Kearny's divisions of Pope's army. Pope had retreated from Manassas to FairfaxCourt House and Jackson was dispatched by Robert E Lee to cut off his communications with Washington. Jackson fell heavily upon Pope's flank, which resisted him stoutly and finally repulsed his attack. Many lives were lost on both sides, however, and among the dead was General Kearny, an old and experienced Union commander. Research Battle of Chantilly