Era
19th century
80
20th century
37
Civil War, 1861-1865
31
To 1775
29
18th century
24
1976
24
Revolution, 1775-1783
24
21st century
20
Colonial period, ca. 1600-1775
20
1796
19
1990
19
1764
16
1793
16
1978
16
1706-1790
15
1977
15
1979
15
1980
14
1789-1797
13
1996
13
1794
12
1765
10
1788
10
1809
10
1810
10
1819
10
1975
10
2000-2099
10
1775-1865
9
1778
9
1995
9
1644-1718
8
1756
8
1787
8
1811
8
1815
8
1861-1865
8
1863
8
1865
8
1971-1980
8
1985
8
1700-1760
7
1732-1799
7
1775-1783
7
1789
7
1791
7
1799
7
1814
7
1984
7
2002
7
more ...