Mostly quoting myself from a previous answer to a similar question:

The Jews didn't do anything in pre-war Germany to upset the country.

While one could argue that antisemitism goes back even further, Christian intolerance of Jews became systemic in the 4th century CE and got worse from there. A lot of this hostility comes from the idea of deicide - that the Jews were responsible for the killing of Jesus.

People continued to find reasons to discriminate against Jews from then on, including hating them for their economic success, blaming plagues on them, etc.

Martin Luther (remember that Germany was/is very much a Lutheran country) was very antagonistic towards the Jews and called for their oppression or even deaths.

So, while the idea of racial inferiority emerged in the 20th century and was applied to the Jews, it was hardly the only factor precipitating the Holocaust.

Just delete this question. I got my answers elsewhere (hope they are accurate, right?!).

Edit: Seriously disappointed. I should have worded it "What did the Germans THINK the Jews did, that upset the country so badly?". But I didn't. Instead I got a lesson in what happens if you ask the wrong questions the wrong way. It is "forbidden"......

It troubles me greatly that (effectively) an entire country can be convinced into such racism, without having some kernels of truth to hang onto to justify such a position.

And here is the problem of your submission. You operate starting from your assumption, and ask a question based on the truth of your assumption. This creates a 'loaded question', as formulated by your title, which is forbidden by our rules.