Era
20th century
42
1945-
18
19th century
16
18th century
15
17th century
9
1945-1970
8
1918-1945
6
16th century
5
1865-1918
5
1970-
5
1971-
5
21st century
5
To 1775
5
1328-1600
4
1775-1865
4
Since 1900
4
To 146 B.C.
4
To 1500
3
Victoria, 1837-1901
3
1066-1485
2
1564-1616
2
1919-1933
2
1991-
2
2000-
2
Civil War, 1861-1865
2
Revolution, 1789-1799
2
To 332 B.C.
2
-1400
1
1000-1328
1
1185-1600
1
1200-1765
1
1221-1284
1
1516-1700
1
1568-1600
1
1709-1784
1
1783-1865
1
1789-1830
1
1800-1899
1
1809-1893
1
1817-1862
1
1830-1900
1
1835-1919
1
1839-1914
1
1865-
1
1865-1900
1
1868-1918
1
1877-1964
1
1900-1999
1
1912-1945
1
1912-1949
1
more ...