After the Union defeat on 21 July 1861 at the First Battle of Manassas, President Abraham Lincoln appointed Major General George B. McClellan commander of the demoralized army. McClellan organized, trained, and equipped the troops, building a force known after August as the Army of the Potomac. On 20 November 1861, McClellan staged a formal military review here between Hill and Bailey's Cross Roads, attended by Lincoln and members of his cabinet. Occupying about 200 acres, some 65,000 troops, including artillery, cavalry, and infantry units organized into seven divisions, took part in the review, at that time the largest ever held in America.
