HOW ONE DEATH SAVED EUROPE

The flap of a butterfly’s wings can set off a storm— but it can also stave one off. In 1241 the Mongols under Batu Khan invaded Hungary and devastated the country so utterly that for one year the kingdom of Hungary ceased to exist. Initially the other European nations heard only the horror stories of the conquest. The wild Mongol warriors were said to savagely torture their prisoners before killing them. They were said to build pyramids with tens of thousands of their victims’ skulls. The inhabitants of the cities they conquered were butchered if they offered any resistance. But as the Golden Horde of Batu Khan continued to move westward, the horror stories became witness accounts. A grandson of Genghis Khan, Batu Khan conquered Kiev and the city-states of Russia before defeating the Polish army and the Teutonic Knights as well as the Hungarians. “On December 11, 1241, the Mongol warrior Batu Khan was poised to take Vienna and destroy the Holy Roman Empire,” says Yale historian Timothy Snyder. “No European force could have kept his armies from reaching the Atlantic.” But in early 1242, the defenders of Vienna could not believe their eyes when the Mongols simply broke camp and sounded the retreat. It would be many years before the Europeans would discover the reason for the Mongol withdrawal—caused by an event thousands of miles away that seemed of little importance to Europe at the time. The son and successor to Genghis Khan, Ögedei, had died at Karakorum, the capital of the Mongol Empire. The first to call himself khagan (“great khan”), Ögedei had been known as a man given over to lasciviousness and alcohol and is said to have died during a drinking bout. Though wars often continue even after the death of a great leader, in this case the butterfly’s flapping wings resulted in significant upheaval. Mongolian law required the other khans to take part in a kurultai (general assembly) in order to choose Ögedei’s successor. For Batu Khan it was not only a matter of honor to participate but also a question of personal power. Seeking dominion over the Mongols, he crossed Russia to return home. And once again there was a flap of butterfly wings, bringing rain to Eastern Europe. Recent climate research has revealed that 1242 was such a wet year in the region that enormous quantities of grain rotted. And so thousands of men in Batu Khan’s Golden Horde died of malnutrition— making a second invasion of Europe impossible.