Constantine defeated -- effects on the empire's borders and politics

Most of the discussions about a reverse outcome at Milvian Bridge i see here often focus on the development of christianity as a religion.
But, here, i'll like to ask: what are the effects of an absent constantinian restoration on the Roman Empire as a whole?
How would the empire be divided? Would a tetrarch like Maxentius or Licinius end up unifying the whole empire under his thumb, like Constantine IOTL, or is a divided empire more plausible?
I've seen some people bring up an earlier abandonment of Britain and germanic barbarians gradually chipping off roman territory in Gaul. Could this happen?
Would the sassanid persians end up deciding to venture into roman territory?
What about Byzantium? Without the upgrading of the city into the massive urban center that has been Constantinople IOTL (and still is, as Istanbul), what happens?
If the huns still come, then how will the non-christian romans react?
 
Last edited:
My gut says a slightly longer division before another union attempt.
I'm not sure after that. Either a cycle of division and union, or a longer lasting union.
 
My gut says a slightly longer division before another union attempt.
I'm not sure after that. Either a cycle of division and union, or a longer lasting union.
Maybe Licinius makes a deal with Maxentius after defeating Maximinus Daia, deciding to split the empire in two?
 
I can definitely see a deal between Licinius and Maxentius being done. I'm not sure however how willing either of them is to go along with it for very long, especially given Maxentius isn't the most stable of imperial partners. Granted, I don't think Licinius (or any of the other tetrarchs, honestly) had the same ambitions Constantine had for sole rule of the entire empire, but he might find having a different partner of his choice to be a more satisfactory alternative. As for the development of Constantinople, I'm sure Byzantium will still see significant buildup, though it's an open question if it will replace Nikomedia as an eastern capital-that's really hard to speculate on, since it's not like Constantine is the only person who saw it's strategic value-that had been recognized since its founding. Just depends if anyone else has the same idea he has and decides to make it their main base.

Another interesting thing is relations with the Sassanians and the Goths. Constantine is largely responsible for the break down in relations with the Sassanians that led to the 40 or so years of intermittent conflict that was a big drain on Rome-including, of course, diverting Roman resources right at the time of the Goths crossing the Danube. You'll probably end up with some alterations in Gothic politics with Licinius having his own policy towards the Goths and perhaps favoring different leaders-I imagine at some point the Goths will still be pushed to seek refuge across the border, but not perhaps at the same time (how desperate they actually were when they crossed, and how much of it was opportunistically choosing the time when the Romans were least able to corral them is up for debate), and certainly not following the same disastrous results.
 
Top