Era
20th century
420
18th century
227
19th century
211
1961-1970
150
17th century
132
1991-2000
118
1951-1960
75
1971-1980
71
2001-2010
70
1981-1990
69
16th century
54
21st century
47
1921-1930
39
500-1400
38
1931-1940
37
1685-1750
35
1941-1950
34
1770-1827
30
1564-1616
24
15th century
24
1756-1791
21
2011-2020
19
1911-1920
16
1749-1832
15
1685-1759
14
1759-1805
13
1732-1809
11
1813-1883
11
1833-1897
10
1882-1971
10
1901-1953
10
1929
10
To 1961
10
1799-1837
9
Civil War, 1861-1865
9
1794-1827
8
1809-1865
8
1862-1918
8
Early modern, 1500-1700
8
Revolution, 1775-1783
8
To 500
8
1788-1866
7
1874-1954
7
1902-1979
7
1948-
7
-approximately 1540
6
1220-1263
6
1631-1700
6
1797-1828
6
1810-1849
6
more ...