German Invasion of Poland
Germany invaded Poland, and Britain and France declared war on Germany, beginning the Second World War. The Soviet Union attacked Poland from the east.

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After annexing Austria (1938) and dismembering Czechoslovakia (1939), Hitler demanded Danzig and the Polish Corridor. In August 1939 Germany and the Soviet Union signed a non-aggression pact whose secret protocol divided Eastern Europe between them.
On 1 September German armies, led by tanks and aircraft, poured into Poland; on 3 September Britain and France declared war. Soviet forces entered from the east on 17 September and Warsaw surrendered on 27 September. Poland was partitioned and occupied by the two powers.