Imagine having to choose between Nazis and Commies. The choice would boil down to the most basic things. Race and language. Whichever evil empire is closest to your race and who speaks your language.
While related to the Germans in terms of language were the Austrians, Dutch, norwegians, Danes and Swedes and English -- and the Dutch, norwegians, Danes and English fought against the Germans.
Racially all were Indo-Europeans, so Sh!tler's Aryan idea was insane -- there are more blue-eyed blondes among Poles than among Germans