So, playing a three-quarters-coop (aka, pretty much coop, but with a lot of bartering about nonsensical reasons as to why X should get involved for Y's war) as Bohemia/Sweden/Muscovy, me playing as the first of the three went full on Hussite. Which has a pre-reformation destabilizing effect on the HRE. Didn't help when the actual Reformation kicked off and all 7 centers of Reformation were inside of the HRE borders...
Long story short, the only remaining Catholic country is Ansbach and with the ruling Emperor (said OPM Ansbach) not having a heir, the Electors had to look... a bit further to find an eligible Catholic nation they didn't feel threatened by.
It's still hilarious they didn't even consider Castille or Aragorn though.
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