As Germany modernised there was a struggle between a traditional typeface called Fraktur and a more simplified typeface called Antiqua which had been used in other countries for centuries. It became something of a culture war with Fraktur seen as either a more patriotic Germanic option or an outdated relic. The Nazis initially favoured it, but then decided that practicality (particularly in occupied countries not used to Fraktur) was more important and Fraktur was declared to be a Jewish invention and phased out.

u/kieslowskifan has written a more detailed answer in this thread:

https://www.reddit.com/r/AskHistorians/comments/3pn8wi/comment/cw7sqhy