When the Venetian merchant Marco Polo got to China, in the latter part of the thirteenth century, he saw many wonders—gunpowder and coal and eyeglasses and porcelain. One of the things that astonished him most, however, was a new invention, implemented by Kublai Khan, a grandson of the great conqueror Genghis. It was paper money, introduced by Kublai in 1260.
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July 14, 2020