On the use Fraktur in general: It really seems to have taken off in the second half of the 19th century. In the Biedermeier era (roughly equivalent to Regency)

On the use Fraktur in general: It really seems to have taken off in the second half of the 19th century. In the Biedermeier era (roughly equivalent to Regency) it's predominantly Latin writing, both in books and hand written documents. Interestingly, the use of Fraktur in the Nazi era was first discouraged in media targeting international audiences (Signal, etc), before it was banned domestically. (I have no idea, if there's a connection or if this was rather a matter of the whims of the factions in charge, as in "Führerprinzip". The latter was really a stand-in for chaos and divide et impera, as there would have been always parallel organisational strains, fighting for the favor of the next level in the hierarchy.) Generally, regarding the aesthetics of the regime, the party line favored the plain, straight, ortholinear as opposed to skewed aspects or the overly ornamental. However, this was subject to favorism and various factions in the regime. (E.g., while the (in)famous shots of Leni Riefenstahl's films would have been in violation of these aesthetic principles and thus should have been deemed "undeutsch", these became pretty much the show case of the regime.) Again, I'm not sure, if there's a connection, but it may provide a hint for why Fraktur fell out of fashion with the regime. Regarding the "ß" ligature, this predates Fraktur and wasn't specific to German writing. (E.g., there are 15th century Italian examples.)