Columbia subject headings:
Harvard subject headings:
Benton, Thomas Hart, 1782-1858
Fremont, John Charles, 1813-1890.
Slavery--Political aspects--United States--History--19th century
United States--History--1815-1861.
United States--Politics and government--1815-1861.
Princeton subject headings:
United States--Politics and government--1815-1861.