Era
20th century
25
17th century
15
19th century
10
1719-1795
7
1706-1781
6
1900-1999
6
21st century
6
1808-1893
5
1949-
5
1800-1899
4
18th century
4
1902-1943
4
1942-
4
1944-
4
1957-
4
16th century
3
1700-1799
3
1724-1806
3
1869-1877
3
1899-1961
3
1950-
3
1961-
3
2000-2020
3
Commonwealth and Protectorate, 1649-1660
3
Cretaceous
3
Elizabeth, 1558-1603
3
To 1500
3
1649-1660
2
1795
2
1809-1882
2
1822-1885
2
1893-1973
2
1900-2099
2
1913-2004
2
1924-
2
1928-2005
2
1931-
2
1938-
2
1948-
2
1954-
2
1954-2014
2
1955-2010
2
1977-
2
Charles II, 1660-1685
2
Civil War, 1861-1865
2
Medieval, 500-1500
2
Paleozoic
2
Stuarts, 1603-1714
2
-1531
1
-1898
1
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