Era
20th century
225
19th century
67
21st century
41
Civil War, 1861-1865
26
Colonial period, ca. 1600-1775
17
Revolution, 1775-1783
14
18th century
10
1929
10
1564-1616
7
Civil War, 1936-1939
7
1933-1945
6
1945-
6
Elizabeth, 1558-1603
6
1547-1616
4
1804-1864
4
1822-1913
4
1853-1890
4
1867-1957
4
Anglo-Saxon period, 449-1066
4
German occupation, 1940-1945
4
Republic, 1912-1949
4
Revolution, 1789-1799
4
War of 1812
4
1452-1519
3
1533-1917
3
16th century
3
1743-1826
3
1767-1845
3
17th century
3
1816-1855
3
1819-1891
3
1886-1957
3
1910-1946
3
1945-1955
3
1949-
3
2000
3
2007
3
2008
3
Louis XIII, 1610-1643
3
Revolution, 1917-1921
3
Richard I, 1189-1199
3
-1400
2
10 B.C.-54 A.D.
2
1027 or 1028-1087
2
1079-1142
2
1412-1431
2
1485-1547
2
14th century
2
1507-1536
2
1564-1642
2
more ...