Era
1945-
Since 1945
33
20th century
10
1945-1953
6
1918-1945
4
1933-1945
4
1945-1989
4
Since 1940
4
Soviet occupation, 1940-1941
4
1960-
3
1960-1980
3
1980-
3
Since 1918
3
Since 1939
3
1789-1945
2
1944-1989 (Polska Ludowa)
2
1945-1955
2
1945-1970
2
1945-1980
2
1949-
2
1953-1985
2
20e siècle
2
Occupation, 1939-1945
2
Revolution, 1956
2
(1905-1982)
1
1850-1937
1
1882-1939
1
1885-1977
1
1887-1947
1
1891-1970
1
1893-1898
1
1896-
1
1899-1970
1
1900-1999
1
1900-2000
1
1904-
1
1905-1982
1
1914-
1
1917-
1
1918-1959
1
1920-
1
1921-
1
1925-
1
1929-1948
1
1931-
1
1933-1989
1
1936-1945
1
1939-1945 (Occupation)
1
1944-1989 r
1
1945-1948
1
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