The Fall Of Rome And Climate Changes

[DanM]

First of all, this entire thread is an exercise in speculation. I am not an expert in science or history. I'm just guy with too much time on his hands who likes to daydream about "What if scenarios". I'm just putting it out there to see if anyone knows anything that would either prove or disprove what I am about to suggest. Also if you want to comment on my speculations or take them in a direction that I have not considered, then that would be great too.

 

I was watching TV last week (I believe the history channel or one of the discovery science channels) and they were talking about a mini ice age that we expereinced from 1350 to 1850. During this period, global temperatures were, on average 4 to 5 degrees cooler than today. That might not sound like a lot, but it was enough to dramatically affect the viability of crops like grains, grapes, etc. They also talked about how the preceding 500 years had been a period of higher temperatures. Globally the temperatures were 5-7 degrees warmer. During this period, I believe they talked about how wine growing in England was so common that French lords complained of it in some official document that have survived until today. If I remember correctly, they also mentioned something about 500 year cycles of things going from cold to warm. If anyone else actually saw this show, maybe you can give a more precise account of the things I am trying to describe here.

 

The proof they offered was both scientific and historical. The scientific part was based on deep sea core samples that counted the numbers of various types of microbes in different layers. Supposedly these things are very sensitive to temperature and the ratios really change within certain narrow temperature ranges. So they basically count the various types of microbes in each segment of the ocean core sample and can make precise estimates on what the temperatures were like at different times. The historical proof was a series of documents like the one mentioned above where they describe crops being raised in areas where they would not be viable today in a manner that is consistent with the core sample temperature estimates.

 

As for how this relates to the fall of Rome (at least in the west), here goes my theory. If these temperature fluctuations occur in approximately 500 year cycles, then it is entirely possible that somewhere between 300 and 400 AD an earlier mini ice age occured. If so, then a lot of things would have happened that could explain many of the events we all know about. First, the east germanic and asiatic barbarian tribes may have migrated towards the warmer mediteranian climates because their own regions no longer provided a viable environment for their pastoral societies. That might help explain why the pressures on the Roman borders became so intense when compared to the previous 3 centuries. Second, if regions like Gaul, Germany, Panonia and Britain became cooler, then its probable that the less developed agricultural methods of the time would have led to a breakdown in the economies of those regions. So instead of the general malaise that many people attribute to the western roman empire at this time, maybe it was an economic breakdown due to climate changes that impaired their ability to grow cash crops like wheat and wine. If you are a big roman landlord and your tennants cannot grow anything except turnips and cabbage because of the climate changes, then you will probably make a lot less income than you did when they could grow more marketable products such as wheat and wine. And, of course, tax revenues would go down dramatically since taxes in kind were common around this time.

 

It might also explain some of the motives for the religous unrest of the period that eventually led to the rise of Christianity. If the climate had failed in many regions of Europe, then it is entirely possibly that many people could have attributed it either to the disfavor or impotence of the old gods. Just my speculation of course, but I think the social and economic unrest that would have followed a mini ice age starting in the the 4th century would have been a likely catalyst for religous upheaval within the Empire.

 

So let me know what you guys think. Like I said earlier, this whole thing is an exercise in speculation. Maybe my assumptions are plausable and maybe they are not. But the possible ways this could help explain the motives for many actions we only know about in a general way such as the barbarian invasions of the empire are really exciting to me. It could help us attach a "why" to the "who and what" that history records.

 

If you have any information that could either prove or disprove the climate fluctuations mentioned on the TV program then I would enjoy hearing your thoughts. Also, if you have any comment on how these climate changes might have affected the motives of the Romans or their barbarian neighbors to the north, I would enjoy hearing those as well.

Edited November 29, 2005 by DanM

[Pantagathus]

'What if' scenarios are a cornerstone of scientific inquiry and only some extreme cases are without merit...

 

That being said, it just so happens that there appears to have been a major climatic event ~535AD. If I remember correctly from what I read it was supposedly volcanically triggered. Supposedly Krakatau?

[Neos Dionysos]

Nice what if theory, this could be a great reasoning for the massive migrations of peoples from the north and the spread of Christianity using the reasoning you described. Also, another major point to consider, if these flucuations occur every 500 years of so we can argueably debate of other great catasphroses. Using a 100 variation, we go from 300-400ad, to also in 200-100bc of which during this period we do know of several great migrations of Germanic peoples into Gaul, and Roman frontiers and allied lands. In each case they were looking for new lands to settle in perhaps it had become to harsh to live in the northern regions if a mini-ice age occured. Now, if push back the time table some more, to 700-600bc and once more to 1200-1100bc, (again these are varations and I am willing to bet it could be 500-700 years in between each of these events in climate), we have the arrival of the "Sea Peoples'" to the 'civilzed world who came from various parts all over the place. Perhaps this great migration of people was triggered by this change in climate and with this great migration of people looking for new lands to call home they destroyed the society and culture of the Late Bronze Age. If we push the time once more back another 500 or so years to around 1700-1600bc, we have recorded dates of again great migrations of people from Inner Asia again. Perhaps you have stumbled upon something few even consider as a possibility for the breakdown of society for the massive influx of migrating peoples. Afterall, such migrations are not only recorded in Europe but also around the same time in China when Rome was experiencing this. So this is not an isolated event, but a world-wide one. I think this theory should be pursued and I know you have greatly peaked my interest in this idea to where I am going to try and find out more and corelate the data.

[sullafelix]

Indeed this is quite a good theory with a lot to merit further study. You might be interested to know that certainly one thing that has been noticed in the archaeological record for large parts of Italy are changes in the patterns of alluviation in river valleys. We know for instance that large parts of the most fertile land in Etruria started to flood from the end of the second century AD onwards and that this process got worse and continued through into the medieval age. What caused this is uncertain but it has to be assumed that either greater rainfall or man made deforestation had something to do with it, or possibly both. Certainly this affected the kinds of agriculture available.

 

However, be careful with the concept of the wine driven rural economy, it is thought that some of our figures now must be wrong because we think that the Roman Empire would have been swimming in wine if we use the figures of people like Columella and Cato. Archaeologically this is hard to prove, because vineyards rarely leave much trace in the archaeological record.

 

There is also extensive rural depopulation in the later empire which had much more to do with social and political reasons than anything else.

 

That said, an inability to grow traditional crops in Italy and other parts of the mediterranean basin would also have profound economic and scoial consequences. I would say this could prove to be quite an interesting part of the overall picture. Have a look into paleaobotanical and osteoarchaeological studies of the relevant time periods. I would recommend a look at Graeme Barker's "A mediterranean Valley" which is a summary of the Biferno River Valley Survey.

[M. Porcius Cato]

What was impact of climate change in Northern Africa?

[DanM]

I agree that climate changes cannot be used in isolation to reason anything. If they can be proven or at least supported as credible possibilities, then these climate fluctuations could be used in combination with things such as:

 

timelines of development in agricultural techniques

social pressures such as the rise of great landowners, opressive taxation and overall government corruption as the Imperial administration consolidated

political devlopments within the empire and outside of it.

 

I only suggest that climate changes could be a big piece of the puzzle and not the full answer.

 

For example, I remember the TV show that inspired this line of thought talked extensively about the creative ways the English of the 14th & 15th centuries altered their crop selection once the colder, more violent weather patterns made previous staple crops less reliable. If the techniques of agriculture were less able to adapt in the 3rd or 4th century, then it puts a totally different element into the mix of why the west expereinced so much political and religous instability in the 3rd and 4th centuries. Once again, I am not saying this is the whole story. I am just saying it would be a very important piece of the puzzle if it could be proven to have occured.

 

We tend to put off all reasons for the fall of the west on things that can easily be observed from the relatively few historical documents that survived and I believe that is a lazy way to go about things. When we stop looking for explanations other than those that are easy and convenient, we create a huge blind spot in our analysis of the historical period. I guess what I am saying is that its crazy to think that everything we cannot put our hands on easily remained static and had no effect upon the events of history.

 

Thats why all of the speculation on why the Empire failed annoys me when it stays on such as superficial level as talking about generals, emperors, military tactics and equipment, etc. I just think there is a lot more to this thing than the superficial places where we all (myself included) spend most of our time. Maybe the climate theory is useful an maybe its not, but I still believe that many of the keys to the fall of Rome lie off the beaten path.

Edited December 3, 2005 by DanM

[DanM]

What was impact of climate change in Northern Africa?

 

This is pure speculation on my part, because I do not remember the TV show addressing north africa specifically. But I would assume that higher levels of rainfall and cooler temperatures would have made agriculture more productive in areas like modern day Tunisia, Lybia and Algeria. I think there is a lot of historical evidence that would back this up when you look at the many accounts regarding grain production in this region.

 

Of course I know there were many other factors in play other than climate, but once again it may have been an important factor in the agricultural success enjoyed in the region at this time.

 

Nice what if theory, this could be a great reasoning for the massive migrations of peoples from the north and the spread of Christianity using the reasoning you described. Also, another major point to consider, if these flucuations occur every 500 years of so we can argueably debate of other great catasphroses. Using a 100 variation, we go from 300-400ad, to also in 200-100bc of which during this period we do know of several great migrations of Germanic peoples into Gaul, and Roman frontiers and allied lands. In each case they were looking for new lands to settle in perhaps it had become to harsh to live in the northern regions if a mini-ice age occured. Now, if push back the time table some more, to 700-600bc and once more to 1200-1100bc, (again these are varations and I am willing to bet it could be 500-700 years in between each of these events in climate), we have the arrival of the "Sea Peoples'" to the 'civilzed world who came from various parts all over the place. Perhaps this great migration of people was triggered by this change in climate and with this great migration of people looking for new lands to call home they destroyed the society and culture of the Late Bronze Age. If we push the time once more back another 500 or so years to around 1700-1600bc, we have recorded dates of again great migrations of people from Inner Asia again. Perhaps you have stumbled upon something few even consider as a possibility for the breakdown of society for the massive influx of migrating peoples. Afterall, such migrations are not only recorded in Europe but also around the same time in China when Rome was experiencing this. So this is not an isolated event, but a world-wide one. I think this theory should be pursued and I know you have greatly peaked my interest in this idea to where I am going to try and find out more and corelate the data.

 

Is there any chance you could share some links to the information you mentioned here? Anyone passing through this thread might benefit from your references to additional information.

 

Thanks.