Approximately 300,000 Polish prisoners of war were captured by the USSR during and after the " Polish Defensive War " . Almost all of the captured officers and a large number of ordinary soldiers were then murdered ( see Katyn massacre ) or sent to Gulags . Of the 10,000 – 12,000 Poles sent to Kolyma in 1940 – 41 , most prisoners of war , only 583 men survived , released in 1942 to join the Polish Armed Forces in the East . Out of General Anders ' 80,000 evacuees from Soviet Union gathered in Great Britain only 310 volunteered to return to Soviet-controlled Poland in 1947
Katyn massacre
Katyn massacre
Gulag