Why would Catalonia and Occitania be one province? The Pyrenees mountains make for a pretty strong natural border. Catalonia doesn't trace back to ancient Rome but the middle ages. It's one of the medieval Christian kingdoms that fought with the various Islamic regimes that ruled southern Spain until it was subsumed into Aragon (which was later merged with Castile.) Prior to that they were all part of a unified Visigothic empire.

With the exception of Roussilon and a few other bits of southern France that were once part of Catalonia/Aragon (https://en.wikipedia.org/wiki/History_of_Spain#/media/File:5...). Before that some of the area was part of the Umayyad Caliphate at their peak (https://en.wikipedia.org/wiki/History_of_Spain#/media/File:M...). Before that is was part of Visigothic Hispania (https://en.wikipedia.org/wiki/History_of_Spain#/media/File:H...). Also, unlike much of Spain, Catalonia was never under Carthaginian control.

So for much of history Catalonia and parts of Occitania were tied together to varying degrees.

The Pyrenees mountains have been a natural border splitting the two regions basically forever. Also, Occitania is doing slightly better than most of Spain, likely due to the proximity and earlier acquisition.

As for the rest of France, Caesar conquered Gaul sixty years earlier, slaughtering up to a million Gallic people. That's the kind of thing that can set your economy way back.

Ah yes the Pyrenees I forgot about them.

In the news I keep hearing about how closely related Occitan and Catalan languages are I figured there was more of a connection geographically.

Caesar had debts to pay - he was the original "too big to fail" debtor ...