In his youth, he organized an informal cavalry company known as the Mountain Rangers, which became part of the 7th Virginia Cavalry ("Ashby's Brigade"). On the outbreak of the Civil War, Ashby and his troopers were assigned to the Virginia Militia command of Colonel Thomas J. "Stonewall" Jackson. Although Jackson's Valley campaign owed much to Ashby's reconnaissance and screening, Ashby was criticized by Jackson for the lax training and discipline of his men. By the time Ashby was killed, leading his men at the Battle of Good's Farm near Harrisonburg, he had received his general’s star. However, Ashby's official rank is contested as the promotion was not confirmed until after his death.