Mongols invade the Jin dynasty of north China

1211

Genghis Khan led his horsemen across the Gobi and through the Great Wall, shattering Jin field armies at Yehuling. The steppe riders learned siegecraft from captured Chinese engineers, a lesson that would make their grandchildren unstoppable from Hungary to Hanoi. The invasion unleashed a quarter century of devastation across the North China Plain that reduced its population by nearly half.