Will Kürlich Kerl
Banned
What happens if there's a personal union between Sweden and Brandenburg, sometime around or before the 30 Years' War?
Kaiseren Christina?
Is Brandeburg and Prussia in a personal union yet by the time Gustav Adolf made his debut in the HRE's political affairs?
So I guess in this case Prussia is just gonna end up as a Polish-Lithuanian vassal.
Though with the complicated Vasa lineage at the time, the Swedes would have a fair argument for claiming that throne as well IIRC.