https://digitalcommons.lsu.edu/cgi/viewcontent.cgi?referer=h...

TL;DR (it's a 213 page grad thesis) Old Germany used to be basically Hufflepuff, a simple-minded, loyal, obedient rustic bumbler who's too stupid to really be a threat or even much of a partner. New Germany arose post-German unification and especially post WW1, where the stereotypes shifted to the modern more sinister concept of a nation of amoral mad scientists and clockwork soldiers - largely as an attempt to justify Germany being the great rival of England.