Era
20th century
1,544
1900-1999
754
19th century
484
21st century
254
1939-1945
226
18th century
220
Civil War, 1861-1865
209
1800-1899
189
2000-2099
108
Revolution, 1775-1783
88
1700-1799
79
1945-
78
17th century
68
1861-1865
64
1900-2099
60
1951-
55
1945-1989
53
1800-1999
50
1939 - 1945
47
1933-1945
46
1900 - 1999
45
1949-
45
1914-1918
44
1946-
43
1989-
40
Since 1945
39
1941-
38
Colonial period, ca. 1600-1775
38
1948-
35
1943-
34
1939-
33
1960-
30
1961-1975
30
16th century
29
1934-
29
1950-
28
1953-
27
To 1500
27
1775-1783
26
1931-
26
1947-
26
1952-
26
1956-
25
1980-
25
1942-
24
1955-
24
1958-
24
1924-
22
1936-
22
1944-
22
more ...