Era
1809-1865
8
1917-1963
7
20th century
7
1945-
6
1861-1865
4
1900-1999
4
Civil War, 1861-1865
4
1933-1945
3
1945-1989
3
Colonial period, ca. 1600-1775
3
Since 1945
3
1783-1865
2
1865-1950
2
1874-1964
2
1897-1971
2
Revolution, 1775-1783
2
(1912-1998)
1
1600-1775
1
1600-1783
1
1736-1799
1
1758-1831
1
1769-1859
1
1775 - 1783
1
1775-1783
1
1777-1852
1
1783 - 1865
1
1819-1898
1
1822-1913
1
1843-1923
1
1846-1848
1
1846-1930
1
1847-1920
1
1861 - 1865
1
1865 - 1989
1
1865-1901
1
1865-1989
1
1873-
1
1881-1954
1
1883-1969
1
1887-
1
1887-1976
1
1890-
1
1908-1973
1
1912-1998
1
1914-1983
1
1915-
1
1919 - 1933
1
1919-1933
1
1929-1933
1
1963-1969
1
more ...