 He then resumed command of Brigade 3, of the Defenses South of the Potomac XXII Corps (Union Army).Tidball was mustered out of the volunteers on September 26, 1865.On December 12, 1864, President Abraham Lincoln nominated Tidball for appointment to the grade of brevet brigadier general of volunteers, to rank from August 1, 1864, and the United States Senate confirmed the appointment on February 20, 1865.