AHC: Duke of Moctezuma de Tultengo becomes the King of Spain

Someone played to much Crusader Kings...

In a word, impossible. Not going to POD lands, cause it would be both hialrious and creepy regarding this challenge, Earth would become flat before sucession rules would allow the Duke to be king.
For instance : the first male offspring, if not the first female, if not the closest male relative of the former king.

Seeing how matrimonial alliances are far more common with foreign lines in order to make alliances, treaties, claims, rather than their own colonial nobility (whatever its origin, spanish or indian, it was despised in Spain) we have odds being quite close of 0. With a (-) sign before.
 
I wouldn't quite say impossible, but it's certainly to the level of extreme coertion to make it happen. The only scenario I can picture which might happen is 'minor daughter of the Spanish Royal family marries the Duke. Some time later Spain is occupied by an invading power and to gain legitimacy they put the Duke (a distant relative, therefore, of the Royals) on the throne because he's pro-them.'

But this requires a huge amount of work to make happen, so we're basically looking at something that's got a less than 0.1% chance of happening.
 
We had this happen in the Progress, Decline & Hope future history timeline with a future Duke marrying one of Crown Prince Felipe's daughters. Their son became King of Spain.
 
We had this happen in the Progress, Decline & Hope future history timeline with a future Duke marrying one of Crown Prince Felipe's daughters. Their son became King of Spain.

I'm inspired by this. I wonder if it can happen before 1900 and also if they have a chance at the Mexican throne while they're at it.
 
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