James Monroe (April 28, 1758 July 4, 1831) was the fifth President of the United States (1817 1825). His administration was marked by the acquisition of Florida (1819); the Missouri Compromise (1820), in which Missouri was declared a slave state; the admission of Maine in 1820 as a free state; and the profession of the Monroe Doctrine (1823), declaring U.S. opposition to European interference in the Americas, as well as breaking all ties with France remaining from the War of 1812.