From the princely household to imperial missions
The History of the Ming identifies Zheng He as a native of Yunnan who served Zhu Di while he was Prince of Yan. He assisted in the struggle through which Zhu Di took the throne and subsequently rose within the eunuch establishment. The biography also calls him the Sanbao Eunuch.
In 1405 the court appointed Zheng He and Wang Jinghong to lead an overseas mission. The fleet sailed from the Liujiagang area, prepared further in Fujian and continued toward Champa and other ports. Officials, soldiers, interpreters, medical personnel, clerks and sailors supplied the skills needed to sustain the commander's work.
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Diplomacy, trade and armed force
Missions between 1405 and 1433 are conventionally grouped as seven voyages. Their routes connected Southeast Asian ports with the Indian Ocean. Calicut served as an important commercial and onward-routing centre, while detachments reached Hormuz, Arabia and East Africa. Proclamations, seals, presents and the transport of foreign envoys formed part of the diplomatic programme.
The voyages also used force. Zheng's biography describes the capture of Chen Zuyi at Palembang and interventions in Sri Lanka and Sumatra. Ma Huan's accounts, meanwhile, detail prices, contracts, currencies and products. These sources place military intervention and commerce alongside the ceremonies of imperial diplomacy.
Nanjing service and the surviving accounts
After Yongle's death, the Hongxi emperor ordered Zheng and troops from the maritime expeditions to defend Nanjing in 1425. The Ming biography treats this as the beginning of that defensive appointment. A renewed commission under Xuande subsequently sent Zheng and Wang Jinghong overseas again, following a period of changed priorities.
Zheng's career survives through several kinds of record. Alongside court biography are Ma Huan's Yingya Shenglan, Fei Xin's Xingcha Shenglan and Gong Zhen's Xiyang Fanguo Zhi. The court account emphasizes commissions and rewards; the companions' writings preserve more of the interpretation, negotiation and local information involved in carrying them out.