Era
Quaternary
36
20th century
12
19th century
8
Civil War, 1861-1865
5
Cretaceous
5
Jurassic
4
18th century
3
Cambrian
3
Ordovician
3
Precambrian
3
Proterozoic
3
Revolution, 1775-1783
3
16th century
2
1789-1815
2
1945-1989
2
1976-2000
2
Mesozoic
2
Ottoman Empire, 1288-1918
2
Partition, 1995
2
1081-1453
1
1268-1492
1
1492-1870
1
1564-1616
1
1648-1715
1
1800
1
1809-1882
1
1860
1
1862-1865
1
1865-1890
1
1865-1921
1
1866-1895
1
1868-
1
1868-1945
1
1869-1877
1
1871-1918
1
1876
1
1882-1971
1
1891-1953
1
1912
1
1921-1981
1
1929
1
1943-
1
1954-
1
1972-
1
1973-1988
1
1976 - 2000
1
1985-1995
1
1991-
1
356-323 B.C.
1
43 B.C.-17 A.D. or 18 A.D.
1
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