According to the Polish Institute of National Remembrance , Soviet occupation between 1939 and 1941 resulted in the death of 150,000 and deportation of 320,000 of Polish citizens , when all who were deemed dangerous to the Soviet regime were subject to Sovietization , forced resettlement , imprisonment in labor camps ( the '' Gulags '' ) or murdered , like the Polish officers in the Katyn massacre
Katyn massacre
Katyn massacre
Invasion of Poland