I'm not saying Philip was the best leader, I'm saying that he is the most reflective of Spanish culture and ideals. He was born into fame and fortune, yet every single thing seemed to wrong for him at every given opportunity even when he made the right choices (lost 3 previously healthy and young wives, lost control of England due to the random death of his second wife, lost many fleets to freak happenstance, lost The Netherlands due to unfortunate timing of his failed invasion, etc), and even in the face of the universe seemingly determined to kick him into the ground he didn't back down or slow his roll he continued to fight and strive without losing his spirit. He is very much a reflection of the "machismo" attitude of masculine strength and determination in the face of any odds or circumstances prevalent in Spain and passed onto its colonial empire, for better or worse.
Secondly, while I don't consider Philip the best leader, and in fact I think Isabella would've been the better pick (would've DEFINITELY traded Catherine's appearance for Isabella's for female representation), I think the civilopedia really does undersell him and constantly focuses on his failures without taking into account any extenuating circumstances and barely acknowledging his successes. It brings up his failed invasion of England without bringing up the fact that it was delayed for a year due to Francis Drake (mostly by luck) managing to sneak past the entire Spanish seaborne navy all the way around Spain until they hit Cadiz (near Gibraltar and almost as far away from England as possible for Iberia) and were able to wipe out many of his best warships while they were trapped in harbor a-la Pearl Harbor, then they failed to mention the fact that once the fleet got going they were absolutely battered by freak storms in the middle of July that forced many of Philip's heaviest galleons to break formation or even dock completely leaving his fleet out of position and poorly equipped when they finally arrived, and of course the moment they DID arrive the winds shifted in England's favor giving them a decisive advantage. Then while it mentions HIS failed invasion it completely omit's ENGLAND'S failed counter invasion which was equally as disastrous despite having everything go in England's favor. It mentions him repeatedly going bankrupt yet doesn't mention all the riches he brought into Spain from his funding of colonial expeditions and how he was the one who kept digging Spain out of debt from prudent trade, loans, and good old fashioned imperialist exploitation of the colonies. Finally while it does mention his funding of the arts it really undersells its influence by only mentioning his stash of private pieces in El Escorial rather than all the public works funded around Spain. While Philip certainly made a lot of mistakes (invading England in the first place was a bad move, even if things went well for his fleet and he conquered the country it would have still locked down a huge chunk of his armies and navies for decades that would've gained him absolutely nothing but religious brownie points) the civilopedia seems to go out of its way to screw him over (typical
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