Era
1961-1975
55
20th century
52
19th century
37
1945-
36
Since 1945
34
Civil War, 1861-1865
30
1900-1999
26
1981-2001
26
1800-1899
25
2001-2009
25
21st century
25
1989-
22
1993-2001
15
Since 1989
14
1971-1981
13
1945-1989
12
1981-
11
2000-2099
11
1861-1865
10
18th century
9
1969-1974
9
1981-2009
9
2001-
9
1900-2099
8
2009-2017
8
20e siècle
8
1783-1865
7
1961 - 1975
7
Since 1981
7
1961-1971
6
1993-
6
20e siècle
6
Geschichte
6
1789-1815
5
1900 - 1999
5
1971-
5
1980-
5
1980-2020
5
2001-2017
5
Since 1980
5
1700-1799
4
1981-1989
4
1989-1993
4
Colonial period, ca. 1600-1775
4
Constitutional period, 1789-1809
4
Revolution, 1775-1783
4
1775-1783
3
1789-1809
3
1865-1877
3
1918-1945
3
more ...