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1939 in Poland
Conflicts in 1939
World War II invasions
Battles and operations of World War II involving Poland
Military history of the Soviet Union during World War II
German occupation of Poland during World War II
Germany–Soviet Union military relations
Wars involving Poland
Eastern European theatre of World War II
Military campaigns involving Germany
Invasions of Poland
Invasions by Germany
Invasions by the Soviet Union
Germany–Poland military relations
Military history of the Second Polish Republic
Germany–Poland relations (1918–1939)
Invasions by Slovakia
Wars involving Slovakia
Germany–Soviet Union relations (1918–1941)