[snovymgodym]

> since modern Germany is a very synthetic unification of what were historically very different sovereign nations

This is fairly revisionist. Germany is no more synthetic than most other modern European countries in that regard. The lands of modern Germany were more culturally and linguistically unified than say, France or Spain (which had more diverse minority languages that were suppressed, e.g. Catalan, Basque, Occitan, Breton).

Virtually everything that is now Germany (and lots that isn't) was part of the same polity, the Holy Roman Empire, for roughly 1000 years before being dissolved by Napoleon in 1806. Yes, it was highly decentralized even for the time, but the fact that there was a common language in the core lands was not lost on people at the time, and a gradual informal standardization of the written language was already taking place during this time.

So Germany's unification in 1871 was essentially re-unifying lands that had been part of the same state for centuries before, only this time they did it under the justification of the then-fashionable concept of the nation state and with a centralized power in control of the whole thing.

Unfortunately for everyone, that centralized power was Prussia.