* [[Aragon]] can also form a Personal Union over [[Castile]] through the Aragonese [[Aragonese_events#The Iberian Wedding|Iberian Wedding Event]] if Aragon is controlled by a player. Aragon can later take a decision to inherit Castile and form Spain.
* [[Aragon]] can additionally form a Personal Union over [[Navarra]] if their 1444 heir, Joan II, ascends to the throne while he still rules in Navarra. (They are the same person.)
* [[Spain]] can form a Personal Union over [[Portugal]] through the [[Spanish events#The Portuguese Crown|
Portugese Crown Event]] between 1550 and 1650, if Spain has a royal marriage with Portugal and the Portugese opinion of Spain is atleast 150. This event is very rare (MTTH is 2000 months).
* [[Naples]] can receive an event that allows it to be in a Personal Union under [[France]].
* [[Brandenburg]] can get a personal union over [[Prussia]] if Prussia is a vassal of Brandenburg or if Prussia's opinion of Brandenburg is at least +100. (This event can still fire even if Prussia is a vassal of another country).