Era
19th century
38
Civil War, 1861-1865
32
20th century
22
1775-1865
21
1865-1950
11
1951-
11
Revolution, 1775-1783
10
1865-
5
1865-1877
5
1783-1865
4
1857-1861
4
18th century
3
Eocene
3
1815-1861
2
1863-1877
2
1865-1900
2
1865-1933
2
1924-
2
1945-
2
1945-1989
2
1981-2001
2
1989-
2
21st century
2
Cretaceous
2
Quaternary
2
To 1863
2
To 1900
2
War of 1812
2
1767-1845
1
1790-1866
1
1790-1866,
1
1806-1870
1
1807-1870
1
1811-1884
1
1815-1875
1
1816-1894
1
1818-1867
1
1820-1890
1
1823-1886
1
1835-1930
1
1860
1
1865-1898
1
1865-1918
1
1877-1934
1
1882-1945
1
1884-1972
1
1889-1945
1
1893-1897
1
1901-1953
1
1903-1942
1
more ...