There it is on the tin. What's the earliest possible date for an independent and sovereign Kingdom of Germany or other German state that isn't the Holy Roman Empire (i.e. a unified and reformed Empire doesn't count)? It has to encompass at least two thirds of the 1871 German Empire, but could include Austria as well.
Bonus points if the German state is still part of the Holy Roman Empire (i.e. unified within the Empire)
Bonus points if the German state is still part of the Holy Roman Empire (i.e. unified within the Empire)