China's Great Armada

From National Geographic

The greatest seafarer in China's history was raised in the mountainous heart of Asia, several weeks' travel from the closest port. More improbable yet, Zheng was not even Chinese—he was by origin a Central Asian Muslim. Born Ma He, the son of a rural official in the Mongol province of Yunnan, he had been taken captive as an invading Chinese army overthrew the Mongols in 1382. Ritually castrated, he was trained as an imperial eunuch and assigned to the court of Zhu Di, the bellicose Prince of Yan.