Era
20th century
991
1900-1999
338
19th century
331
21st century
178
1975-
109
1800-1899
102
2000-2099
86
Civil War, 1861-1865
60
1980-
52
1929-1968
48
1865-1877
45
1945-1989
45
To 1964
43
1877-1964
41
Since 1975
37
1868-1963
35
1865-1918
34
1989-
31
2009-2017
30
1945-
28
1800-1999
26
18th century
26
2001-2009
23
2008
23
1861-1865
20
1809-1865
19
1933-1945
19
To 1863
19
Colonial period, ca. 1600-1775
17
1863-1877
16
1900 - 1999
16
1900-2099
16
1946-
16
1960-1980
16
Since 1900
16
1993-
15
1818-1895
14
1963-1969
14
1964-
14
1924-1987
13
1951-
13
1918-1961
12
1980-2020
12
Since 1980
11
To 1999
11
1961-1969
10
1783-1865
9
1925-1965
9
1964-1975
9
1973-2020
9
more ...