Historical Period
20th century
147
1945-
87
21st century
85
19th century
61
1970-
48
1980-2020
28
18th century
23
1960-1980
21
To 1500
21
1918-1945
15
1980-
14
17th century
13
1989-
13
1865-1918
11
To 146 B.C.
11
1945-1995
10
1933-1945
9
16th century
8
1981-2001
8
2000-
8
To 1865
8
1947-
7
To 332 B.C.
7
1066-1485
6
1918-1932
6
2001-2009
6
1976-2002
5
1991-
5
1900-1999
4
1917-1945
4
1918-1933
4
1945-1989
4
1945-1991
4
1971-1981
4
1976-2000
4
1981-1989
4
1990-
4
2002-
4
Civil War, 1861-1865
4
To 1830
4
To 476
4
To 640
4
1268-1559
3
1288-1918
3
1868-1912
3
1898-1967
3
1917-1970
3
1949-
3
1950-
3
1955-
3
more ...