Era
20th century
45
1865-1950
38
19th century
34
1951-
27
Civil War, 1861-1865
11
1800-1899
8
1865-1877
8
1863-1877
7
To 1964
7
1865-1900
5
1865-1951
5
1877-1964
5
1800-1950
4
1865-
4
1865-1898
4
1775-1865
3
1783-1865
3
1818-1895
3
1856-1915
3
1868-1963
3
1887-1940
3
1929-1968
3
Since 1865
3
Since 1900
3
Since 1951
3
1800-1999
2
1861 - 1950
2
1865-1918
2
1865-1933
2
1865-1999
2
1885-1954
2
1900-1999
2
1918-1961
2
1933-1945
2
1945-1989
2
1989-
2
To 1775
2
To 1999
2
1783-1933
1
1800-1918
1
1808-1884
1
1832-1900
1
1835-1933
1
1850-1918
1
1861-1950
1
1861-1999
1
1882-1945
1
1886-1954
1
1890-1965
1
1898-1974
1
more ...