Professor Kyle Harper

But volcanoes are like this really powerful thing. And I don't mean like the Iceland volcano that dribbles out smoke and disrupts some air travel. As significant as that is, every century or two, even Vesuvius that erupts in the first century and buries Pompeii and Herculaneum is not a big eruption.

It's really big if you're in Pompeii and you're broiled to death, but it doesn't cause the global climate system to wobble. Whereas the big eruptions of 536 and 540 In this Roman climate optimum period, you have three or four centuries where there's only one really, really big eruption. It's aligned with the death of Julius Caesar. One doesn't cause the other unless you're like a

It's really big if you're in Pompeii and you're broiled to death, but it doesn't cause the global climate system to wobble. Whereas the big eruptions of 536 and 540 In this Roman climate optimum period, you have three or four centuries where there's only one really, really big eruption. It's aligned with the death of Julius Caesar. One doesn't cause the other unless you're like a

It's really big if you're in Pompeii and you're broiled to death, but it doesn't cause the global climate system to wobble. Whereas the big eruptions of 536 and 540 In this Roman climate optimum period, you have three or four centuries where there's only one really, really big eruption. It's aligned with the death of Julius Caesar. One doesn't cause the other unless you're like a

polytheist and think that Vulcan was mad about the assassination or something. It's just pure coincidence. But you have this really long phase where you don't have big volcanic eruptions, where it looks really relatively stable. It is warmer in core parts of the Mediterranean.

polytheist and think that Vulcan was mad about the assassination or something. It's just pure coincidence. But you have this really long phase where you don't have big volcanic eruptions, where it looks really relatively stable. It is warmer in core parts of the Mediterranean.

polytheist and think that Vulcan was mad about the assassination or something. It's just pure coincidence. But you have this really long phase where you don't have big volcanic eruptions, where it looks really relatively stable. It is warmer in core parts of the Mediterranean.

And so you do have this kind of background of stability, which arguably creates a kind of condition of favorable climate, of prosperity, of agricultural productivity. This is a farming society. Even in the Roman world, 80% of people at least are working in agriculture. They're very dependent on the immediate climate context.

And so you do have this kind of background of stability, which arguably creates a kind of condition of favorable climate, of prosperity, of agricultural productivity. This is a farming society. Even in the Roman world, 80% of people at least are working in agriculture. They're very dependent on the immediate climate context.

And so you do have this kind of background of stability, which arguably creates a kind of condition of favorable climate, of prosperity, of agricultural productivity. This is a farming society. Even in the Roman world, 80% of people at least are working in agriculture. They're very dependent on the immediate climate context.

It has to be warm enough for the growing season to enable crop growth, and it has to be wet enough, but not too warm and not too wet. The Roman climate optimum seems to be this phase where you have a relatively stable climate, which probably means a relatively stable food supply, which probably means a population that's relatively able to contend

It has to be warm enough for the growing season to enable crop growth, and it has to be wet enough, but not too warm and not too wet. The Roman climate optimum seems to be this phase where you have a relatively stable climate, which probably means a relatively stable food supply, which probably means a population that's relatively able to contend

It has to be warm enough for the growing season to enable crop growth, and it has to be wet enough, but not too warm and not too wet. The Roman climate optimum seems to be this phase where you have a relatively stable climate, which probably means a relatively stable food supply, which probably means a population that's relatively able to contend

by pre-modern standards with the pool of infectious diseases that are out there. And then there may be elements of luck. I mean, this is one of the things that's most fascinating about this is that history involves, you know, you've got to be lucky and good if you want to build a stable empire. And there is just this pure element of contingency of luck that comes into history.

by pre-modern standards with the pool of infectious diseases that are out there. And then there may be elements of luck. I mean, this is one of the things that's most fascinating about this is that history involves, you know, you've got to be lucky and good if you want to build a stable empire. And there is just this pure element of contingency of luck that comes into history.

by pre-modern standards with the pool of infectious diseases that are out there. And then there may be elements of luck. I mean, this is one of the things that's most fascinating about this is that history involves, you know, you've got to be lucky and good if you want to build a stable empire. And there is just this pure element of contingency of luck that comes into history.

Well, again, to go back to our very first line of conversation, It's always both the human and the natural. So there are really important human factors.

Well, again, to go back to our very first line of conversation, It's always both the human and the natural. So there are really important human factors.

Well, again, to go back to our very first line of conversation, It's always both the human and the natural. So there are really important human factors.

There's important things going on inside Roman society, inside the way the empire works, inside the relation between the center and the periphery, between elites and workers, geopolitically, between the Romans and the peoples across their frontier, especially across the northern frontier.