Isabella of Castile marries John II of Portugal...

An Emperor

Banned
And Ferdinand II of Aragon marries Sophie Palaiologos or Charlotte of Cyprus.

What happens from there? Would Aragon seriously claim the Byzantine throne if he married the former, or Cyprus and eventually Naples if he married the latter?
 
The combination of Castile's most fiercest monarch and the terrifying king of Portugal is almost to awesome to imagine as a combo. They would take over the world! Or burn it down, it could go either way.
 
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