Historically, as we all know, Spain and the Holy Roman Empire were both ruled by the same monarch, Charles V, resulting, on paper, in one of the largest and most far-flung empires ever known.
Your challenge is to create a similar situation, replacing the HRE with the ARE (Actual Roman Empire); aka, the Byzantines.
Here are your parameters:
- The Byzantine portion of the realm must be centered around Constantinople, and must be fairly considered legitimate by its people, and should, at minimum, control the entirety of the Aegean coastline. A surviving Latin Empire, no matter how popular it may or may not be with the people, only counts if there are no comparably powerful 'proper' Byzantine Remnants (an isolated Trebizond is okay, a powerful Nicaea is not). That said, a strong preference goes for the actual Byzantines.
- The Colonial portion of the realm can be any plausible colonial power (Iberian, French, British, Scandinavian, even Dutch), but a similar preference will go towards those countries that would have some reasonable proximity to the Mediterranean. It should also be the largest colonial empire in the New World.
- You have free reign with matters regarding religion, within reason.
- The discovery of America can happen early, but no earlier than the 15th century (isolated events like Erikson aside).
- The fewer butterflies, the better.
- POD no earlier than... 1203 sounds good.
Well, that should be it. Whats the best scenario you can come up with, and where do you see it going?