Era
Revolution, 1775-1783
22
Civil War, 1861-1865
19
Colonial period, ca. 1600-1775
15
20th century
13
18th century
8
19th century
6
Revolution, 1917-1921
6
1760-1789
4
1900-1999
4
1917-1921
4
1945-1980
4
1809-1817
3
1898-1946
3
1945-
3
1732-1799
2
1783-1865
2
17th century
2
1917 - 1921
2
1918-
2
1918-1938
2
1939-1945
2
1944-1989 (Polska Ludowa)
2
1945-1989
2
1945-1992
2
1973-
2
Constitutional period, 1789-1809
2
German occupation, 1940-1945
2
New Plymouth, 1620-1691
2
Occupation, 1939-1945
2
Since 1918
2
War of 1812
2
1600-1699
1
1648-1789
1
1667?-1708
1
1714-1738
1
1714-1837
1
1743-1826
1
1762-1878
1
1775-1783
1
1780-1791
1
1789-1815
1
1809-1865
1
1815-1872
1
1816
1
1822-1893
1
1861-1865
1
1865-1898
1
1940-1991
1
1976-2009
1
1979-
1
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