 From 1849 to 1861, Mott held a variety of jobs in New Jersey with the Lamberton Port, Bordentown, Delaware & Raritan Canal Company, and the Bordentown Bank.In the summer after the start of the Civil War, Mott was appointed the lieutenant colonel of the 5th New Jersey Infantry, part of the Army of the Potomac.His regiment fought in the Peninsula Campaign and shortly after the Battle of Williamsburg he was promoted to colonel and command of the 6th New Jersey Volunteer Infantry.