Era
20th century
103
19th century
84
To 1964
18
Civil War, 1861-1865
17
1975-
16
18th century
13
1865-1950
12
Colonial period, ca. 1600-1775
9
1775-1865
8
1917-
8
1877-1964
7
1951-
7
1964-1975
6
1980-
6
1743-1826
5
1863-1877
5
1887-1940
5
1945-
5
To 1863
5
-1911
3
1806 or 7-1857
3
1809-1865
3
1921-
3
1945-1953
3
1946-
3
1960-1980
3
1964-
3
19th cent
3
Revolution, 1775-1783
3
1783-1865
2
17th century
2
1800-1899
2
1818-1895
2
1838-1899
2
1839-1871
2
1861-1865
2
1865-1918
2
1865-1951
2
1868-1963
2
1871-1938
2
1898-
2
1900-1999
2
1901-
2
1914-
2
1916-
2
1921-2010
2
1925-
2
1925-1965
2
1929-1968
2
1944-
2
more ...