>>20906016A bit off-topic. I would like to see such a state in an alternate scenario. If during the Great Migration it was not Byzantium that survived, but the Western Empire. And if, just like post-Arab Byzantium, it found itself impoverished and surrounded by a ring of enemies, constantly forced to fight for its existence.
It would literally be the Imperium from WH40K. A semi-feudal state on the ruins of a once-glorious civilization. Poor and filthy, plunged into the religious obscurantism of the ubiquitous Catholic Church, yet still too powerful to fall. On the ruins of once prosperous cities now stand grim castles and fortresses, where local warlords (Dux Romanum?) defend against raids by Germans from the north, Muslims from the south, Slavs from the east, and Vikings from the sea. Sometimes they fight each other for power and influence, but they all unconditionally recognize the supreme authority of the Emperor (REAL Roman, some Flavius Awesomus Maximus Aemilian), who has firmly reestablished his seat in Rome, which has acquired a sacred status for the citizens (now de facto subjects) of the Empire...
https://youtu.be/J7iHyFogz0E?feature=shared 
