Jon Schofield was an American soldier who held major commands during the American Civil War. He later served as U.S. Secretary of War and commanding general of the United States Army. During the Civil War Schofield was a major in a Missouri volunteer regiment and served as chief of staff under Major General Nathaniel Lyon. He spent time in command of the Army of the Frontier. His military career was long and distinguished. His memoirs are an excellent look into the military history of the United States.