New research suggests that Genghis Khan may have been aided by (natural, not man-made) climate change in his quest to run rampant over most of Eurasia. Studies of tree-rings from the period between Khan's ascendance, conquest and death showed conditions that benefited a Mongol horde.
What exactly are conditions favorable for Eurasian conquest in the 13th century? The answer, as surmised by researchers from West Virginia University and Colombia University, 'is warm and wet.' Using the tree-ring data, gathered near Genghis Khan's capital of Karakorum, the researchers determined that Mongolia was seeing unusually high levels of rainfall for a period of roughly thirty years in a row. This may not sound like a big deal, but it led to the longest string of rainy years there measured in the past thousand years.
Khan's army was mounted, and these ample rains may have ensured that grazing was plentiful for man and beast alike. This would have meant an increase in both manpower and horsepower, the two most important ingredients to your average Mongol horde. We don't mean to discount Khan's strategic brilliance, but bumper crops, a boom in the horse population and a cooperative climate certainly compounded with his other natural gifts.
The next step in the research is to investigate lake sediments, which provide a climatological and biological record stretching back as far as tree rings, or farther. Scientists will be looking for a specific type of fungus that thrives in horse poo, which would provide more evidence that an animal population spike was part of Khan's genius. Ultimately, it may very well be that the natural flow of climate change helped lead to the largest contiguous empire in history.
Via The Economist