The Stalinist Soviet Union established "special settlements" where the "socially harmful" or "socially dangerous" who included ex-convicts, criminals, vagrants, the disenfranchized and "declassed elements" were expelled to.
Similar to Nazism, Stalinism in practice in the Soviet Union pursued ethnic deportations from the 1930s to the early 1950s, with a total of 3 million Soviet citizens being subjected to ethnic-based resettlement.
German and Soviet soldiers during the official transfer of Brest to Soviet control in front of a picture of Stalin in the aftermath of the invasion and partition of Poland by Nazi Germany and the Soviet Union in 1939.
Margarete Buber-Neumann in her memoirs from both communist (1937–1940) and nazi (1940–1945) concentration camps found methods of both regimes to be very similar.
These ethnically-based deportations reflected a new trend in Stalinist policy a "Soviet xenophobia" based on ideological grounds that suspected that these people were susceptible to foreign capitalist influence, and based on a resurgent Russian nationalism.
After Nazi Germany declared war on the Soviet Union in 1941, the Soviet Union initiated another major round of ethnic deportations.
Soviet authorities claimed the territory was "rich soil for the Japanese to till" – implying the Soviet suspicion that the Koreans could potentially join forces with the Japanese forces to unite the land with Japanese-held Korea.
Over 170,000 Koreans were deported to remote parts of Soviet Central Asia from September to October 1937.
The comparison of Stalinism and Nazism, which was conducted on a theoretical basis by political scientists during the Cold War, is now approached on the basis of empirical research, since greater information is available.