Jews the majority of Germany? Excuse me? In 1933 there were about half a million Jews in Germany. By 1939 it was half of that. Plenty of statistics exist on the racial demographic of Germany in this era, and I recommend the racial state to look at the composition of Roma, Jews, and disabled in this era. Most of Europe's Jews were in Poland, territory gained after 1939, but there were of course Poles in Germany given the fact that Poland was part of Germany until 1918.

The racial makeup of Germany is a difficult question, as racial scientists inflated the problem to inoculate a sense of Volksgemeinschaft in the German people. The disabled formed a part of Germany's racial makeup if you listened to someone like Walther Gross, and so did criminals, the asocial, homosexuals etc. If you mean more traditional racial demographics, then like I said Jews only formed half a million in Germany proper, and also a significant mixed polish minority (and also poles on the fringes of the state, like in Silesia). If anything, Germany lost most of their ethnically diverse territories after the first world war, so no racial demographics in Germany were not a massive factor only insofar as racial scientists inflated the issue. Lebensraum and racial science is what lead to the 2nd world war; the desire for the East (Drang nach Osten) and the belief that the people there were unworthy of life (Lebensunwertes Leben). Germany became more diverse as they gained more territory-territory which the Germans deserved to inhabit and thus the destruction of those who did inhabit it were justified in their eyes.

​

Sources. The Racial State. Histoire de L'antisemitisme, Origins of the Final Solution.