
These periods comprise a largely un-rediscovered history. The fascination of the dominant university narrative with militarism also leaves out vast areas on the periphery, where a lot of innovation began. We know about the Silk Road and the exchanges between East and West that it augured. We also know something of the slave and precious metal industries, and the cultural influences that flowed between North and South.
The Mongol Empire, established by Genghis Khan in 1206 and lasting through the 13th and 14th centuries — generally considered in the west as a part of the descent in the post-Roman world into barbarism — was the largest contiguous empire in the world, covering 16 to 22 percent of the Earth's total land area, and dominating a population of 100 million. Having that much land, as we shall see, can have implications for Earth’s biomechanical systems, depending on the management style of the small group of Khans in control.

Genghis Khan came up with a number of military innovations that fueled his army’s prowess in battle. He organized his troops into cadres of ten men, divided his imperial guard into day guards and night guards, dispensed with most privileges of class and family, ended women’s slavery and permitted them to divorce, promoted religious freedom, encouraged literacy, and stopped internecine conflict in order to better concentrate on Mongolia’s external goals.
Khan’s sons and grandsons were just as ambitious but not as wise as their patriarch, and when he died in 1227, leaving them an empire twice the size of Rome, they expanded outwards in all directions and, rather than promoting social equality and other benefits for their new constituents, were more inclined just to massacre them.


It is estimated that 30 to 60 million people were slaughtered under the rule of the Mongol Empire, roughly 30 to 60 percent of the Empire’s population at its peak. Bubonic Plague factored into the decline in Europe, but the populations of Russia, Hungary and China fell by half in fifty years. To speed their way towards future conquests, Mongols punished urban centers that refused to surrender. So, for instance, after the conquest of Urgench in present Turkmenistan, perhaps the wealthiest city on the Silk Road at the time, each of 20,000 Mongol warriors was required to execute 24 civilians. After the fall of the Mongolian Empire in China, 30 million were killed in the violent overthrow of the Yuan Dynasty.
If it is somehow imagined by right-wing US Congressmen, New York Times columnists, and other climate deniers that somehow we humans are the victims of natural cycles of sunspots and freakish weather, the legacy of the Golden Horde should settle that question. We, as a species, are profoundly entangled with planetary biomechanical cycles, including weather.
As we described in The Biochar Solution, the Colombian Encounter, which may have directly caused the deaths of 100 million native inhabitants of the Americas, wiping away all traces of their cultures, languages, and domesticated plants and animals, also changed the climate of the planet, triggering the Little Ice Age from the 16th to 19th Centuries, including three particularly cold intervals at 1650, 1770 and 1850.
According to studies performed by the ARVE Group in Lausanne, Switzerland, the forests of the Americas, growing in the deep black earths built over millenia by native milpa agriculture, sequestered 35-40 GtC between 1525 and 1600 following the Columbian Encounter. These new findings, based on newer datasets and better models, are considerably higher than earlier estimates and in the range needed to explain the 7-10 ppm CO2 drop observed.
We’ve referred to the work of William Ruddiman who first linked the Black Death to a decrease in agricultural activity that had climate-altering impacts. Ruddiman is author of Plows, Plagues, and Petroleum: How Humans Took Control of Climate, which propounded the "early anthropocene" hypothesis, the idea that human-induced changes in greenhouse gases did not begin in the eighteenth century with advent of coal-burning factories and power plants but date back to our early agrarian ancestors 8000 years ago. By 3000 years ago, cumulative carbon emissions caused by anthropogenic land cover change were between 84 and 102 GtC, translating to about 14-20 ppm increase of atmospheric CO2.

Left to cyclical variations in the orbit and tilt of the Earth, we should by rights be on glide descent into another glaciation. Land use changes, beginning with the deforestation of Egypt and China, arrested that trend and ever since has kept us in the steady holding pattern we call the Holocene.
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Eocene Arctic. That little creature with the furry tail in the tree branches was our most direct ancestor. |
The overdue glaciation has now been cancelled, and in its place has been scheduled the second coming of the Palaeocene-Eocene Thermal Maximum with crocodiles in the cypress and redwood swamps of the Arctic, palm trees in Greenland, Antarctica a subtropical rainforest, and sea surface temperatures at the equator within 5 degrees of boiling. Given the unprecedented slope of the rising exponential curve of change, and the sheer volume of fossil carbon now being withdrawn from land and banked in the atmosphere and oceans, the new PETM may be just a brief train stop on the track to Hell. Venus, move over, here we come.
Except, on that Eastern hilltop, surveying his battlefield, with eyes cast toward the setting sun, stands the great and mighty Khan.

We now have the example of two great genocidal conquerors turned climate heroes — Christopher Columbus and Genghis Khan. In both cases, the greenhouse effect was shown to have direct correlation to changing human population and land use. It should be no surprise that today, with a world population North of 7 billion, boosted by high-GHG-emission technological lifestyles, that we are experiencing a runaway greenhouse warming.
It should also be evident that the only viable way out is a forest path.
But what about clean coal or the Kyoto Protocol, you may ask?
The carbon sequestering techniques available to us can be divided between those that require further research and development, conventional financial methods of capitalization, or an industrial infrastructure that may not survive economic contraction (for example, ceramic honeycomb filters coated with immobilized amine sorbants deployed on coal-burning power plants), and those that require none of these and can be begun at the smallest scale, using few or no special tools, without benefit of loans, savings, or even an exchange currency.
Tree planting is a more viable strategy post-petrocollapse, than is the manufacture of artificial trees and their deployment over the scale of land area required to make a difference.
Forests also confer advantages not available to fossil-energy-made structures, such as resilience, self-repair, ecosystem services, preservation of biodiversity, etc.
What we have learned from Genghis Khan is that forests actually can work to bring climate back into a second Holocene. What we don’t yet know is whether they can provide sufficient food to support Anthropocene populations after petrocollapse. Can we have the regreening, without the gore?
Food forests are a frontier being explored by permaculturists, and while we can see that strategy already working to sustain large populations in the tropics, whether it can do so outside the tropics is an open discussion. Work in edible forest design by Eric Toensmeier, David Jacke, Martin Crawford and others is showing steady progress. Geoff Lawton and Brad Lancaster’s pioneering work in greening desert-scapes will also contribute, as will the work of Alan Savory and Wes Jackson in productive savannah and prairie ecologies.
It may be a good thing that tropics and deserts hold the most promise for building food forests. We will be experiencing a greater abundance of both in the decades to come, until we collectively grasp these concepts and go back to gardening our planet, the way we always have.