Era
20th century
122
1900-1999
47
19th century
40
1975-
24
21st century
24
1887-1940
22
1800-1899
15
Since 1975
9
2000-2099
7
Civil War, 1861-1865
7
To 1863
7
1800-1999
6
1868-1963
6
1865-1950
5
1877-1964
5
1900-2099
5
Colonial period, ca. 1600-1775
4
1775-1865
3
18th century
3
1964-1975
3
2008
3
Revolution, 1791-1804
3
1743-1826
2
1791-1899
2
1843-1916
2
1858-1932
2
1861-1865
2
1865-1999
2
1874-1938
2
1875-1935
2
1890-1948
2
1894-1959
2
1897-1962
2
1901-1981
2
1947-
2
1954-
2
1989-
2
To 1964
2
1600-1865
1
1700-1899
1
1743-1803
1
1743?-1803
1
1800 - 1899
1
1842-1901
1
1842-1917
1
1860-1964
1
1861-1945
1
1862-1931
1
1863-1877
1
1877-1999
1
more ...