Elihu Root (February 15, 1845 - February 7, 1937) He served as the United States Secretary of War 1899?1904 under William McKinley and Theodore Roosevelt. He reformed the organization of the United States Army. He was responsible for enlarging West Point and establishing the U.S. Army War College as well as the General Staff. In 1905, President Roosevelt named Root to be the United States Secretary of State. He served in the United States Senate (Republican - New York) from 1909 to 1915. In 1912, as a result of his work to bring nations together through arbitration and cooperation, he received the Nobel Peace Prize.