Era
20th century
140
19th century
95
1900-1999
54
21st century
36
1800-1899
27
18th century
27
1800-1999
18
2000-2099
16
To 1500
15
Civil War, 1861-1865
12
1783-1865
11
1700-1899
9
1933-1945
9
1945-
9
1865-1918
8
1959-
8
1980-
7
17th century
6
1900-2099
6
1989-
6
1870-1940
5
1994-
5
16th century
4
1700-1799
4
1775-1783
4
1783-1789
4
1783-1850
4
1865-1999
4
1918-1932
4
1946-
4
1947-
4
2000 - 2099
4
Since 1945
4
Since 1980
4
1660-1688
3
1743-1826
3
1800 - 1899
3
1811-1896
3
1861-1865
3
1865-1877
3
1865-1950
3
1869-1934
3
1873-
3
1934-
3
1979-
3
1991-
3
1997-
3
2000-
3
2002-
3
Civil War, 1994
3
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