﻿In the last decade, it’s become popular to say that the Mongols,
and the empire’s founder Chinggis Khan in particular, killed so many people that it caused
the earth’s climate to cool. In the last few days I have had the misfortune to have a particularly
irritating video sent to me about it on Tiktok. So, I’ve tracked down the article that made
this claim, and we’re going to evaluate it. The claim was popularized in a 2011 article by Dr.
Julia Pongratz et al., published in the scientific journal The Holocene. In it, Dr. Pongratz notes
how drops in CO2 levels from ice-core samples corresponded to certain dramatic periods of war,
epidemics and destruction, mass casualty events in pre-industrial societies which resulted
in a decrease in agricultural production. Overtime the abandoned farmland is reclaimed by natural
vegetation and trees, and eventually reabsorbs more CO2 from the air. On a large enough scale,
she suggests, this can be observed in regional and atmospheric reductions in the levels of CO2,
which can be measured in the annual build up of snow and ice in the poles.
However there are some caveats here, which is emphasized in her article. Namely, it takes a
very long time, decades or centuries, for this vegetation build up to reach a level where it
is actually collecting more carbon from the air than it discharges through initial decomposition
and soil release. Therefore, in order to have an extensive, measurable impact and perhaps even
global effect, the abandonment of farmland needs to not just be large-scale, but long-term. So
in her article, while the Black Death killed a third of Europe and results in the widespread
abandonment of farmland, the 53 year period she gives for it is too brief for this to have global
effects. Recovery simply begins too quickly for this to be anything other than a small blip.
But then we get to the Mongols; the article notes that the Mongol conquests,
by not just killing 40 million people, but also occurring over a 180 year period,
is the only event where the population is pushed down enough, for long enough, for enough
environmental reclamation to take place to result in notable carbon reabsorption. 700 million tons
worth of carbon, the equivalent of a year’s worth of large-scale coal and oil production today,
as Dr. Pongratz told the Daily Mail in an interview. And the Daily Mail,
as a nice British rag, summarized this with the subtle title of “Genghis Khan the Green!” And
since then, this has been spun into the Mongols killing so many people that so many trees grew,
that earth’s temperature cooled! And what more evidence do you need, since the Little Ice Age
happened in the fourteenth century! Everything was cold and wet! A nice neat little bow.
But let’s take a look at Dr. Pongratz’s claims for the Mongols. Now, I cannot question the science or
formula of her team. I’m no scientist. But I am a historian. So let’s assess what she says about
the Mongol conquests. Firstly, she does not speak about the Mongol conquests as a whole;
rather, the calculation with the Mongols here is focused on the wars in China. It’s from this that
we get the figure of perhaps 40 million killed, which seems supported by Chinese census data,
but we won’t get into that here. Instead, let us look at the date range she gives
and the problems with it. One of the key parts of her argument is
that this population and agricultural decline needs to be large-scale, and long-lasting. So
the Black Death at 50 years is too brief, but the 180 year range she gives for the Mongol conquests
is sufficient. But here’s the question: how long do the Mongol conquests go for?
And here I suspect Dr. Pongratz did naught but a quick google for this, and was given 1380 as
an end date. Why 1380? 1380 itself doesn’t mark a year of significance for the Yuan Dynasty. They
were pushed from China in 1368, Toghon Temür Khaan died in 1370 and the last Yuan holdouts in Yunnan
fell to the Ming in 1382. But 1380 does mark one famous thing; the battle of Kulikovo, an overblown
skirmish between Prince Dmitri Donskoi and the beylerbeyi Mamai of the Golden Horde fought in
what’s now Russia. It’s sometimes claimed as the end of Mongol rule over Rus’, although
it was not that. While it remains popular as a ‘decline-point’ for the Mongols in some circles,
it is not the end of the Mongol conquest. It’s actually much too late for that.
See, the Mongol conquests did not take 180 years. The actual period of conquest,
wherein the Mongols were not just conquering lands outside of Mongolia, but engaging in
large-scale massacres of agricultural populations, at the scale necessary by the article’s argument,
is much shorter. We can measure that roughly from 1208, the first large Mongol attack on the Tangut
Kingdom, to 1279, when Khubilai Khaan’s armies defeated the last of the Song Dynasty holdouts
and completed the conquest of China. While military activities continue past this date,
they are much less common, not on comparable scale, and are rarely accompanied by wholesale
massacre of the civilian populations. Rather, they’re generally on a destruction level closer to
regular warfare in a given region. These campaigns after 1279 do not see any lasting conquests, or
prolonged warfare that results in the depopulation and abandonment of lands for decades, or at least
not enough to measurably impact CO2 levels compared to the fighting of,
say, the exceptionally destructive 1230s. An argument could be made to narrow to the most
destructive period, which is 1210-1260. But sticking with 1208 to 1279, we are left
with 71 years. Recall how the article had the Black Death’s range of 53 years as too short,
despite killing a commonly estimated 75 million people? Well, if we take the
Mongols as killing 40 million people over 71, is that really a greater impact?
There is a further issue with this date range. The keen eyed among you might note Dr. Pongratz’s
supplied range means that the Black Death and Mongol conquests overlap. The Black Death was not
isolated in Europe; in this period it also occured in the lands of the Chagatai Khanate, Ilkhanate
and Golden Horde, and potentially in China too though there is no conclusive evidence for
that. So my question then would be, how would you differentiate, in this overlap, from carbon lost
to land abandoned due to plague, or Mongols, or both? Or the resulting instability? When the Yuan
Dynasty collapsed, there was epidemic, warfare between not just Mongol and Chinese rebels,
but Chinese factions fighting each other for the right to succeed the Yuan. The largest battles are
actually between Chinese armies in this period. Coupled with the possibility of the Black Death
there too, then is it accurate to attribute these deaths to the Mongol conquests after 1340?
This is my problem with these sorts of estimates and claims. They seem to line up really nicely
and accurately when you step very far back from them, but the closer you get, and more detail
you examine them in, it becomes very difficult to ascribe these to single factors. And indeed,
global atmospheric CO2 levels should not be ascribed to single events. The article
notes in its conclusion that many researchers attribute these changes in CO2 levels not to wars,
but to the Little Ice Age, the general climatic trend towards cooler and wetter temperatures
which began in the thirteenth century, and had dramatic impacts in the fourteenth century.
In Europe, for instance, there’s widespread famine and starvation from overly wet and cool weather
before the plague even hits. When it does hit, it’s hitting a population greatly
weakened through malnutrition. Were the Mongols responsible for
cooler temperatures on earth in the thirteenth and fourteenth century?
Almost certainly not; the Volcanic eruption of Samalas in the 1250s, for instance, had a
greater impact on global climate than the Mongols did. The Mongol conquests happened to precede
global cooling trends brought on by the Little Ice Age, and in the early thirteenth century they may
have benefitted from wetter conditions in Mongolia which accompanied these gradual climatic shifts.
The resulting deaths and abandonment of farmland caused by Mongol invasions did probably have some
impact on global carbon levels, but not nearly as dramatic as popularly presented, and personally I
would think it was less than what we may associate with the Black Death. Furthermore, we could point
to the Golden Horde in the fourteenth century, where we see an expansion of farmland in the
Volga steppes to support the growing cities in that region, and other reconstructive efforts
undertaken by various Mongol governments, to suggest the actual amount of agricultural
land left to fallow in parts of the empire is not as extensive as the study implies.
In short, the article’s premise relies on deliberately presenting the Mongol
conquests as almost two centuries of continued, destructive warfare, when in fact we have 70
years of conquest followed by comparatively less destructive raiding, incursions or rebellions.
This is not to minimize or reduce the scale or destruction of the conquests,
but simply accurately report their length of time. In turn, the popular presentation of the Mongols
changing the global climate comes from further misrepresentation of this article and its data,
and making the Little Ice Age a consequence of the Mongols. Please do not learn about history from a
British tabloid or a guy who uses a random google search as evidence in a Tiktok video.
While there was a drop in global CO2 levels, even the original article does not present it as
dramatically as popularly portrayed, and it cannot be unequivocally connected
to the Mongol conquests. Based on the argumentation of this article, if the Black
Death did not make a significant difference in carbon levels, then the Mongol conquests did not
either. The global climate is a massively complex thing not subject to any single factor;
a decrease in agricultural production may be an apostrophe within a larger book. Climate
is a lot harder to influence without millions of cars, factories and those rat bastards at
Nestlé ruining it. While science is a useful tool,
it should not be used in isolation to look at history or humanity. Without sufficient
historical background or context, the hard data of a study can be misinterpreted and brought to false
ends. History and the humanities give science the context it needs to have meaning for humans;
without it you simply have data points. And that’s a roundabout way of saying,
no, Chinggis Khan was not the Greenest conqueror. So please stop sending me tiktoks about it.