Why Rome really fell

I have a related question about this: how to explain the dynastic instability in the Roman Empire?

Well, it wasn't always the case.

First, I'm going to reinforce your case : counting the usurpers (meaning the guys that proclaimed themselves emperors but didn't reached Rome), you can easily double or more the number.

But Rome alternated periods of dynastic stability (not meaning political stability, but including events as Claudius accession to purple, being part of the same dynasty than the previous holder), and periods where the shit just got real.

While every dynasty knows his lot of usurpers, not all were really challenged by it : Theodosians were pretty much certain of holding the imperial authority despite it with an average 20 years reign.

Basically, it's hard to make a general statement over all the dynastical stability.

What was more important for me, was the mode of accession in the throne was basically a Cluedocracy even in the stable periods and not only in the period of crisis as in the IIIrd (where it's almost systematical) : you have an awful lot of emperors being simply murdered by their successors or by their opponants.
 
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