The USSR had a large population of ethnic Germans, especially in the Volga German Autonomous Soviet Socialist Republic, who were distrusted and persecuted by Stalin 1928 to 1948. They were relatively well-educated, and at first, class factors played a major role, giving way after 1933 to ethnic links to the dreaded Nazi German regime as the chief criterion. Very few the Germans involved supported Hitler, but no matter. the tax escalated after the German invasion of 1941.