Edit: I think my confusion is that there’s never been a whole world empire. Shouldn’t that happen if conquering a neighbouring region tends to make you more able to conquer other regions?
Alexander’s empire didn’t last. It seems like shortly after being founded, the Roman Empire has a lot of trouble and then (from my skim of Wikipedia) Diocletian sort of split it in four?
There’s also never been someone with 100% of the money, even though getting money tends to make it easier to get more money. (For example, you can just invest it in an index fund!)
There definitely are ways in which maintaining an empire gets harder the bigger it gets. For example, communication is more difficult over longer distances and higher language barriers. Also, ingroup cohesion becomes harder to maintain when the outgroup is weaker and more distant. And there are of course special cases—e.g. England for the Roman Empire—where holding on to a piece of territory is more trouble than it’s worth. Nevertheless it’s still true that, in most cases, conquering something gives you more resources, military force, etc.
I wrote some interesting speculation on this topic a few years ago. Roughly speaking, large premodern empires seem to consistently max out around roughly the same population size (~60M, with large-but-less-than-a-factor-of-two error bars). The few which manage to get larger than that through conquest rapidly split apart.
One generation. The Mongols were the only empire to get a lot bigger than 50-70M (they capped around 110M), and they promptly split in a war of succession.
There’s also never been someone with 100% of the money, even though getting money tends to make it easier to get more money.
Oh yeah! What’s up with that?
Nevertheless it’s still true that, in most cases, conquering something gives you more resources, military force, etc.
Yeah, that seems to be true. My intuition is still having trouble with the success of converting the conquered military. Wikipedia tells me it was a big deal, and it remains surprising to me
That’s a good point!
Edit: I think my confusion is that there’s never been a whole world empire. Shouldn’t that happen if conquering a neighbouring region tends to make you more able to conquer other regions?
Alexander’s empire didn’t last. It seems like shortly after being founded, the Roman Empire has a lot of trouble and then (from my skim of Wikipedia) Diocletian sort of split it in four?
There’s also never been someone with 100% of the money, even though getting money tends to make it easier to get more money. (For example, you can just invest it in an index fund!)
There definitely are ways in which maintaining an empire gets harder the bigger it gets. For example, communication is more difficult over longer distances and higher language barriers. Also, ingroup cohesion becomes harder to maintain when the outgroup is weaker and more distant. And there are of course special cases—e.g. England for the Roman Empire—where holding on to a piece of territory is more trouble than it’s worth. Nevertheless it’s still true that, in most cases, conquering something gives you more resources, military force, etc.
I wrote some interesting speculation on this topic a few years ago. Roughly speaking, large premodern empires seem to consistently max out around roughly the same population size (~60M, with large-but-less-than-a-factor-of-two error bars). The few which manage to get larger than that through conquest rapidly split apart.
How rapidly?
One generation. The Mongols were the only empire to get a lot bigger than 50-70M (they capped around 110M), and they promptly split in a war of succession.
Oh yeah! What’s up with that?
Yeah, that seems to be true. My intuition is still having trouble with the success of converting the conquered military. Wikipedia tells me it was a big deal, and it remains surprising to me