Era
20th century
661
19th century
252
Civil War, 1861-1865
106
Revolution, 1775-1783
91
1809-1865
63
Colonial period, ca. 1600-1775
56
1900-1999
55
1564-1616
45
1867-1957
43
1929
41
18th century
38
1732-1799
35
17th century
32
1929-1968
32
1939-1945
30
21st century
27
1933-1945
26
1775-1865
20
1919-1972
20
To 146 B.C.
20
1743-1826
19
1945-
18
1946-
18
To 332 B.C.
18
16th century
17
1775-1783
17
1898-1951
17
German occupation, 1940-1945
17
To 1775
17
1917-1963
16
Victoria, 1837-1901
16
1800-1899
15
1858-1919
15
1929-1945
15
1452-1519
14
1822-1913
14
1963-
14
1706-1790
13
1867-1912
13
1871-1948
13
1900 - 1999
13
1818-1895
12
1847-1931
12
1865-1898
12
1950-
12
Elizabeth, 1558-1603
12
1880-1968
11
1897-1937
11
1774-1845
10
1835-1910
10
more ...