Can you give any examples of societies that went to the brink and reversed course? I can't think of any, but I'd be fascinated to learn more about examples who have.
They didn’t entirely “reverse course”, the society changed and evolved at each point, but it remained recognizably Roman. And that’s just the western empire.
But also, pre-imperial Rome, a number of times. The Conflicts of the Orders, the entire late-Republican period from the Gracchi to the final demise of the Republic under Augustus.
And then the Eastern Empire had to reinvent itself multiple times. The near-collapse to the Caliphate. The Norman invasions of the Balkans and the First Crusade. The Fourth Crusade and its aftermath.
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Then in the West, you have a couple brief periods where Rome isn't subject to Eastern Imperial overlordship. Justinian fully reconquers it in the late 500s, and Rome stays nominally part of the Eastern Empire until its brief loss to the Lombards in the 750s. But Charlemange's father, Pepin the Short, reconquered Rome and confirmed the Pope's authority over it. A couple decades later, Charlemagne is crowned Emperor of the Romans. And Rome exists under a constantly shifting balance of authority between Popes and Emperors until the Italian Unification in the late 1800s.
It should also be noted that even before the end of the Western Imperial line in 476, Rome rarely served as the actual home of the emperors since the late 200s.
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So there's an interesting question of whether Rome ever did really fall, before the modern period. I would say "yes", in the sense that after the mid-400s, you never again have a sense of authority over the Mediterranean basin eminating from Rome (or the northern half of Italy). That's what people think of when they think of Rome. There are only brief periods of anything like that, and you never again have multi-generational, institutional authority.
But in other ways, there really is a continual reinvention of political systems that trace their lineage and cultural power to Rome. In that sense, it's kind of like China, which is similarly not really a continuous institution.
Focused on democratic turnarounds so its adjacent to your curiosity - but a great, enlightening read.
Also, the Roman Empire had terrible civil wars and recovered. Until it didn’t.
There are many situations in history when people on one side back down right before shit hits the fan. Another good example of that was British subjugation of India. Doesn't matter how much hot gas Churchill would emit about keeping India forever British, when push came to shove, Clement was sympathetic to India's desire for freedom, and did not choose to plunge the empire into colonial war.
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[1] Which was up the steps to a guillotine, by order of the National Convention.
The thing is, though, they had help recovering, and help stepping back from the brink. Help won't be coming this time. Just as there are no George Marshalls in today's Republican party, and no room for any, there is no one outside the US who will come to our own rescue.
you're not creating a new society from whole cloth, you're taking already battered Big Dogs and getting them back to being Big again (minus the, you know, Nazis and bad actors).
but they were already societies that had cutting edge tech and made serious end-runs at taking over the world.
South Korea would be the only real example of where you took the poor agrarian area and eventually grew it into an asian tiger.
The crisis of the third century could easily have been the doom of Rome, with its crumbling splinter states infighting until they broke apart completely. Instead, the succession of Aurelian, Diocletian, and Constantine were able to build it back into a single unified state, if not so prosperous or dominant as the previous version had been.
The same chaos that took the west might well have claimed the east as well under different circumstances, but over time they were able to restabilize, recover, and start to grow again. If not for the Justinian Plague, the reconquest of Italy might have been an actual success instead of the phyrric one it turned into. If nothing else, they at least managed to hold onto fully half the empire until centuries later when the Arabic conquests began.
And speaking of those early conquests, there was absolutely no guarantee that those wars were something they would survive. The Empire was still recovering from a brutal, generations long war against Persia, which itself did not survive as an independent state. The sieges of Constantinople were harsh and brutal, and could have gone differently, but they held on and slowly regained control of what they could, until the Macedonian dynasty was at least the foremost power in the region once again.
But then they screwed it up, spent some years in decline from a succession of bad rulers culminating in a few key defeats to the Turkish invaders caused in large part by infighting from wealthy elites. After this, they spent most of a generation with various elites selling off bits of the remaining empire to secure a throne whose value continued dropping with each betrayal. This too could easily have been the end, but eventually things stabilized. One of these grasping leaders actually managed to hold onto power and slowly rebuild. Then one lucky crusade later, they actually have much of their pre-Turkish territory back.
Except oops, a grasping member of the imperial family seizes control and drives it into the ground. After that we get a succession of weak emperors unable to deal with the harsh realities of their situation, followed by a series of coups that results in one of the displaced heirs inviting the fourth crusade into empire, which eventually results in the capital being sacked and the empire shattering into tiny city states.
That really ought to have been the end. Except that one of these states managed to regain control, rebuild to a fraction of their old strength, and at least hold most of Greece and Western Anatolia. It was a tiny, tiny fraction of the pre-crusade empire, much less Rome at its height, but they were still able to carve another century or two of stability when all hope had seemed lost.