Growing evidence supports the claim that Zheng He visited America in 1421.
With a fleet of 317 ships and 28,000 men, Zheng He is generally acknowledged as one of the great naval explorers, but how far he actually went remains a matter of dispute.
With 600 years of sailing experience, the Chinese had already developed many tools useful to sailing over great distances - like magnetized compasses and watertight bulkhead compartments of a kind the West would have to wait hundreds of years for.
Importantly, Zheng He's ships, known as junks, included on-board vegetable patches, growing soybeans in tubes all year to provide protein and vitamin C, guarding sailors against scurvy.
But He was probably not the first Asian to sail to America. Most of the world had already been mapped by Kublai Khan's fleet.