Aye, I'm watching 'Isabel' right now and learning quite a bit about Iberian history and am astonished at how badly its represented in EU4
Like how Isabel had to fight a civil war against Marquis Juan Pacheco and his puppet King Henry (the terrible heir Castile has), and how after Henry died his young daughter Juana was used by Archbishop Carillo and Alfonso (king of Portugal) to try and claim the throne of Castile. And like how Aragon was an impoverished and highly feudal realm, with catalan nobles doing whatever they wanted to their peasants and ignoring the crown. And how the Reconquista of Granada was actually instigated by Granada themselves, who then succumbed to civil war.
Amazing how terrible Iberia is represented in EU4. Castile should have it's own war of the roses type disaster to get rid of Henry, at least, and Portugal should not be historical friends with Castile.