1. Germany - pre 1933 - about 900,000 using the Nazi definition of one or more Jewish grandparents. At the end of World War 2 - about 20,000 plus an unknown number of half- and quarter Jews.
2. Poland - 1931 census - about 3.3 million; after World War 2 (in 1931 frontiers) - about 300,000.
3. Soviet Union (plus the Baltic republics) - pre war - about 3.1 million; after World War 2 - about 1.6 million.
The figures for the Soviet Union are less reliable than those for Germany and Poland.