Era
20th century
159
19th century
69
1900-1999
42
1945-1989
36
1989-
34
1800-1899
23
1945-
22
1933-1945
21
21st century
20
2001-2009
19
18th century
15
1809-1865
13
1960-1980
13
1882-1945
12
1963-1969
12
1980-
11
Civil War, 1861-1865
11
1993-2001
9
1946-
8
Since 1945
8
1783-1865
7
1917-1963
7
1939-1945
7
1945-1953
7
1953-1961
7
1961-1963
7
1969-1974
7
2000-2099
7
1971-1981
6
1981-1989
6
1993-
6
2008
6
2009-2017
6
Since 1989
6
To 1775
6
1732-1799
5
1800-1999
5
1913-1994
5
1960-
5
2003-2011
5
Revolution, 1775-1783
5
1775-1783
4
17th century
4
1858-1942
4
1901-1953
4
1961-1975
4
Colonial period, ca. 1600-1775
4
Revolution, 1910-1920
4
Since 1900
4
1743-1826
3
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