Era
Civil War, 1861-1865
23
Colonial period, ca. 1600-1775
21
Revolution, 1775-1783
13
19th century
6
Civil War
4
1775-1783
3
1732-1799
2
1809-1817
2
1809-1865
2
1849
2
1849-1861
2
1861-1865
2
1914-
2
1914-1918
2
20th century
2
Period
2
Revolution
2
Revolution (1775-1783)
2
War of 1812
2
1775
1
1812-1815
1
1815-1861
1
1843
1
1847
1
1853-1857
1
1856
1
1857-1861
1
1863-1877
1
1865-1900
1
1880-1890
1
1893-1897
1
1897-1901
1
1911-
1
1917-
1
1918-1945
1
1960-
1
1979-
1
1979-1990
1
1980-
1
1989-
1
Civil War, 1860-1865
1
Congresses
1
Since 1979
1
War of 1898
1