Era
20th century
39
1900-1999
25
19th century
23
18th century
19
1945-
10
1939-1945
9
1900-1945
7
1800-1837
6
1979-
6
Revolution, 1775-1783
6
Since 1979
6
1914-1918
5
20e siècle
5
1809-1865
4
1918-1945
4
1945-1989
4
1945-1991
4
1975-
4
Civil War, 1861-1865
4
Since 1945
4
1760-1789
3
1917-1945
3
1933-1945
3
1945-1980
3
1980-
3
1783-1850
2
1800-1945
2
1847
2
1860-1918
2
1881-1945
2
1892-1984
2
1898-1946
2
1914-
2
1917-1921
2
1931-1939
2
1934-
2
1939-1975
2
1944-1989 (Polska Ludowa)
2
1945-1992
2
1953-1985
2
1973-
2
1979-1992
2
Civil War
2
Colonial period, ca. 1600-1775
2
Early 19th century
2
German occupation, 1940-1945
2
Revolution (1775-1783)
2
Revolution, 1917-1921
2
Since 1931
2
Since 1934
2
more ...