By revolutionising his army and his ruthlessness in battle, Genghis Khan established the largest land empire in history
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The Great Wall of China proved an inadequate defence against Genghis Khan – he marched his army around it
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In the early 13th century, Wanyan Yongji, mighty emperor of the Jin, sent a message to an upstart warlord who had had the temerity to invade his territory. “Our empire is as vast as the sea,” it read. “Yours is but a handful of sand. How can we fear you?”