The Battle of Chantilly (Ox Hill) took place here on 1 September, 1862, when Union General John Pope's army, retreating after defeat by Lee at Second Manassas, clashed with Jackson's divisions as they attempted to prevent Pope from reaching Washington. Although Union generals Kearny and Stevens were killed, Jackson's men were held off by the smaller Union force. The battle ended the Second Manassas campaign and led to Lee's invasion of Maryland.