Herbert Hoover Mounted Signature with COA. Herbert Clark Hoover (August 10, 1874 – October 20, 1964) was an American engineer, businessman and politician who served as the 31st President of the United States from 1929 to 1933 during the Great Depression. A Republican, as Secretary of Commerce in the 1920s he introduced themes of efficiency in the business community and provided government support for standardization, efficiency and international trade. As president from 1929 to 1933, his domestic programs were overshadowed by the onset of the Great Depression. Hoover was defeated in a landslide election in 1932 by Democratic Franklin D. Roosevelt. After this loss, Hoover became staunchly conservative, and advocated against Roosevelt’s New Deal policies.