Era
20th century
62
19th century
35
1900-1999
31
Colonial period, ca. 1600-1775
23
18th century
22
Civil War, 1861-1865
17
Revolution, 1775-1783
14
1945-
11
1939-1945
10
Revolution, 1917-1921
8
1809-1865
7
1900-1945
7
1951-
7
1800-1837
6
1917-1921
6
1918-1945
6
1945-1991
6
1979-
6
Since 1979
6
1869-1934
5
1914-1918
5
1945-1989
5
20e siècle
5
1786-1853
4
1804-1869
4
1945-1980
4
1945-1992
4
1975-
4
Since 1945
4
War of 1812
4
1760-1789
3
17th century
3
1860-1918
3
1898-1946
3
1917-1945
3
1933-1945
3
1980-
3
Since 1918
3
1590-1679
2
1699-1777
2
1732-1799
2
1783-1850
2
1783-1865
2
1800-1945
2
1812-1815
2
1836
2
1847
2
1881-1945
2
1892-1984
2
1914-
2
more ...