Which Chinese admiral led treasure fleets across the Indian Ocean in the 1400s?

Zheng He, a Muslim eunuch from Yunnan captured and castrated as a boy during the Ming conquest, who rose to command the largest fleets the world had seen - seven voyages between 1405 and 1433, reaching Arabia and the east coast of Africa.

The scale is contested and enormous either way. The fleets carried tens of thousands of men, and the largest ships are described in Ming sources at over 120 metres, which many naval historians think physically implausible for wooden construction and others defend. Even the conservative estimates make them several times the size of anything Columbus sailed sixty years later. A giraffe was brought back to the imperial court and received as a qilin, an auspicious mythical beast.

Then China stopped. After the last voyage the court, under pressure from Confucian officials who regarded the expeditions as eunuch extravagance and preferred spending on the northern frontier, ended them, burned the records and eventually banned oceangoing ships. It is the standard example of a great power withdrawing voluntarily from a capability it clearly possessed, at almost exactly the moment Europe began sailing outward.