Era
Colonial period, ca. 1600-1775
40
19th century
32
Revolution, 1775-1783
20
17th century
19
20th century
18
New Plymouth, 1620-1691
14
18th century
12
Civil War, 1861-1865
9
To 1775
9
1775-1865
7
1817-1862
6
1804-1864
5
1822-1903
5
Paleozoic
5
1735-1826
4
1807-1882
4
Silurian
4
1590-1657
3
1591-1643
3
1732-1799
3
1775-1783
3
1917-1963
3
Cenozoic
3
Cretaceous
3
Precambrian
3
1639-1723
2
1663-1728
2
1735-1818
2
1767-1848
2
1772-1864
2
1773-1838
2
1804-1894
2
1830-1886
2
1834-1862
2
1837-1863
2
1860-1927
2
1929-2018
2
1948-
2
1989-2017
2
21st century
2
Carboniferous
2
Devonian
2
Holocene
2
Queen Anne's War, 1702-1713
2
Tertiary
2
To 1865
2
-1770
1
-1993
1
1566 or 1567-1644
1
1584?-1656
1
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