When it was released, Alfred J Kwak was wildly popular in Germany and I think the Netherlands, too. I still consider it to be one of the most beautifully produced European animated shows from that era. DVD releases were sparse and I don’t think you can stream it anywhere (except some shady YouTube channels that probably are only left alone because the whole thing has pretty much disappeared into obscurity).
Something that I guess is only popular over here is Tatort, which is essentially your typical crime solving series. It’s released every other Sunday and always plays in some German speaking city or town. Quality varies wildly, but that is also sort of what makes it nice to watch, Tatort just hits differently depending on whether it’s the one from Münster or from Wien.
Wildly popular over here is also “die Sendung mit der Maus”, “the mouse program”, maybe. It’s usually a set of entertaining animated or puppeteered shorts, educational segments and few-seconds-long animations of the mouse. It’s been on air for decades.
Alfred J. Kwak was actually a co-production of VARA (NL), ZDF (DE), TV Tokyo (JP) and TVE (ES). Lots of people involved ;).
Didn’t know those German series were popular across the border! Very interesting. And hey, learning a language is never a bad thing, I guess. Sometimes I wish the Germans wouldn’t dub everything.