Well, the HRE doesn't contain the kingdom of Bohemia anymore. I noticed there's a Billung with a claim on the kingdom of Bohemia, so I pushed that claim. I won easily, because the HRE was fighting among themselves for a change (speaking of which, I found that when you're independent you can join wars at will, pretty fun
), so a Billung got the throne. Sometimes it's a surprise what happens when you push a claim:
-the Billung family gets the throne
-the new king gets the county with the capital
-the old king stays duke of the duchy of Bohemia, without the capital
-another Billung already was duke of the other half of Bohemia
-obviously the king of Bohemia can't be vassal of the king of Germany, because the titles are of a similar level
-the kingdom of Bohemia becomes independent (yay!)
-the duchy of Bohemia stays in the HRE (wait what?)
Sometimes the game shows other surprising peculiarities:
I can't revoke his title, because his territory is still de jure part of the HRE. Yet the HRE is in turmoil and doesn't have ANY crown authority... Does it make sense? I don't think anything in regard to the HRE made any sense in reality, so in that regard this mechanic makes sense.
I've encountered a minor disconvenience: I've lost a duchy. I had conquered two duchies that are the jure part of the kingdom of Poland: Silesia and Greater Poland. The kingdom of Poland has an elective monarchy, with the de jure dukes getting a vote. So when the duke of Silesia nominated himself, and the duke of Greater Poland supported his nomination... he became the king of Poland, taking the duchy of Silesia with him. So now there's a Billung on the throne of Poland and a Billung on the throne of Bohemia.