There is a taboo, a subject about which almost nobody talks in the circles of typography, and the few ones who tried to were quickly bashed and sent to oblivion.
The subject is: Paul Renner, Futura, and the nazis.
I'm going to make it short, using the information I have verified, totally or partially: Paul Renner was the director of a printing school in Germany, and He was very close to the Bauhaus movement - though never being officially part of it. In the late 20's, He made some harsh comments on the nazi regime in a book. Subsequently, he was banned from his school when Hitler's powers rose. While most of the Bauhaus people flew out of Germany after it was closed by the nazis, Renner stayed in. In 1941, Goebbels understood that the Blackletter, until then promoted as a vibrant traditional pangermanic font, was too hard to read on the display panels and any outdoor signage, such as roads signs and so on, thus putting a serious brake on Germany's taking over Europe. He then issued the order to ban the use of Blackletter, suddenly described as a "jewish style" (!!), and realized that the sans serif of the Bauhaus era were pretty much sticking to the canons of national socialism. The Third Reich then began to use... Futura. I have some official third reich documents using Futura: letterheads, nsdap handbuch, door signs, even an enigma operating manual. Renner is known for having said that He was very sad about this misuse of Futura, but other sources prove that towards the end of the war, He was working closely with Albert Speer on the creation of an official type for the Third Reich... And Futura was so much associated with the nazi Germany at that time that after the war, Maximilen Vox tried really hard to force Peignot to distribute the font, which He reluctantly did after lots of discussion and after renaming it "Europe", for some years.
It's very hard to get any more info about this era. Every biographer of Renner tends to avoid this gap.