20th century 694 19th century 580 Civil War, 1861-1865 268 1775-1865 162 1951- 125 1865-1877 94 1865-1950 93 1865- 89 18th century 61 1897-1962 57 Colonial period, ca. 1600-1775 43 1865-1951 42 1865-1945 40 21st century 32 1945- 29 1877-1964 28 1918- 28 1863-1877 27 Revolution, 1775-1783 26 1865-1918 22 1809-1865 19 1857-1861 19 1861-1865 16 1905-1989 16 1945-1989 15 17th century 14 1800-1899 14 1909-2001 14 1933-1945 14 To 1964 14 1811-1896 11 1815-1861 11 1899-1979 10 1900-1999 10 To 1775 10 16th century 9 1783-1865 9 1865-1900 9 To 1865 9 1897-1966 8 1903-1986 8 1929-1968 8 1789-1869 7 1908-1999 7 1918-1961 7 1920-1980 7 1929 7 1933- 7 1835-1910 6 1856-1915 6 more ...