Era
20th century
180
19th century
133
17th century
71
1900-1999
66
18th century
50
1800-1899
34
21st century
20
1800-1999
18
Civil War, 1861-1865
14
1585-1626
13
1700-1799
13
1580-1629
12
1863-1951
12
1811-1872
10
1559-1632
9
1600-1699
8
2000-2099
8
1849-1877
7
1931-
7
Revolution, 1775-1783
7
1517-1648
6
Civil War, 1642-1649
6
Colonial period, ca. 1600-1775
6
1809-1865
5
Revolution, 1789-1799
5
To 1775
5
1865-1951
4
1882-1941
4
1902-1981
4
1923-1991
4
1933-1945
4
1951-
4
2001-2009
4
1700-1899
3
1789-1809
3
1800 - 1899
3
1815-1884
3
1854-1926
3
1867-1959
3
1880-1955
3
1891-1957
3
1900 - 1999
3
1901-1953
3
1903-1978
3
1909-1992
3
1918-1945
3
1945-
3
1945-1953
3
1945-1989
3
Since 1900
3
more ...