The Mongols’ fast and furious conquest of Asia and much of Europe in the early 13th Century has been attributed to many factors: superior horsemanship, rigid discipline, devastating archery, and even the ruthless genius of Genghis Khan himself.
But according to researchers from Columbia University and West Virginia University, perhaps the greatest force driving the relentless Mongol onslaught was actually Mother Nature.
A study published in last week’s Proceedings of the National Academy of Sciences suggests that the Mongol’s lightning-fast expansion was preceded by an unprecedented period of mild and wet weather in Central Asia. According to the report, the extraordinary climactic shift, which occurred in the late 12th century, transformed the normally rugged, dry and barren Mongol homeland into a lush and bountiful grassland. This in turn led to a livestock population explosion, particularly among the nomadic warriors’ horse herds. Ultimately, it was the abundance of new mounts that helped power the Mongol conquests of the Eurasian landmass.
Columbia climatologist Neil Pederson and Amy Hessl, a dendrochronologist from West Virginia U, arrived at this surprising conclusion after surveying the telltale rings inside ancient trees in present-day Mongolia. Tree rings are known to be reliable indicators of historic temperature patterns and rainfall levels, among other things.
“The transition from extreme drought to extreme moisture right then strongly suggests that climate played a role in human events,” said Hessl. “It wasn’t the only thing, but it must have created the ideal conditions [to] develop an army and concentrate power.”
Prior to the climatic shift, the Mongols were a divided people — frequently hungry and torn by internal strife. Genghis Khan, who rose to power in 1206, unified the warring factions into a cohesive warrior nation and promptly inaugurated a series of invasions against all of his kingdom’s neighbours. During his 21-years in the saddle, Khan’s armies stormed China, Russia, Korea, Southeast Asia and India, slaughtering millions along the way. His sons would later push on into the Middle East, Persia, and even Eastern Europe, killing millions more and ultimately creating the most expansive empire in recorded history. Researchers believe that Khan’s meteoric rise was a by-product of the odd weather fluctuations, the likes of which hadn’t been seen in Central Asia for a thousand years.
“Before fossil fuels, grass and ingenuity were the fuels for the Mongols,” said lead author Neil Pederson, a tree-ring scientist at Columbia University’s Lamont-Doherty Earth Observatory.
“Where it’s arid, unusual moisture creates unusual plant productivity, and that translates into horsepower,” added Hessl. “Genghis was literally able to ride that wave.”
For more information about the research, check out the full article here.