His reign (1573–1620) was the longest of the Ming dynasty (1368–1644), but his personal qualities made it an irreversibly disastrous one, which his weak and incompetent successors were unable to reverse.
Because he was a child and did not rule personally, the first 10 years of Wanli’s reign went well as his birth mother and his father’s empress cooperated with Grand Secretary Zhang Zhuzheng (Chang Chu-cheng) to supervise his education and direct the government.
All changed for the worse when Zhang died in 1582. Wanli would never appoint strong and capable men to high positions again. In fact as his reign progressed, he let many positions unfilled when their incumbents died or retired, crippling the government.
Wanli became more unpredictable and self-absorbed with time. Between 1589 and 1615 he never appeared at imperial audiences, leaving his ministers and foreign envoys to kowtow before an empty throne. He attended no public ceremonies after 1591, not even his own mother’s funeral. Instead he relied on eunuchs to inform him about affairs and to act as intermediaries between him and his ministers.
He refused to read government reports and official memorials, leaving the state in chaos and upright officials in despair. He was moreover extravagant, spending lavishly on his palaces, clothes, entertainment, and a magnificent mausoleum for his body after death, bankrupting the treasury.
Adding to the burden of the treasury was the by now huge imperial family scattered throughout the land, all supported by lavish grants from the treasury. Wanli was also addicted to food, alcohol, and sex and became so fat that he could not stand unsupported. The dynasty never recovered because his son and successor survived him by only a month.
The next ruler (his grandson) was slow-witted and only interested in carpentry, so he entrusted the government to eunuchs and finally left the throne to his younger brother Chongzhen (Ch’ungchen, r. 1628–44). Chongzhen never had a chance and committed suicide as rebel forces swept into Beijing (Peking), ending the dynasty.
Military problems abounded. Mongols attacked in the north, ethnic minority groups revolted in the south-west, and between 1593 and 1598 the Japanese invaded Korea, a campaign that was only thwarted after China sent a large army.
A more serious threat appeared in the northeast with the rise of the nomadic Jurchens under Nurhaci. Adopting a new name, Manchu, and a new dynastic title, the Qing (Ch’ing), these prior frontier vassals would later replace the Ming dynasty.
On the wider scene, the Wanli reign signaled the emergence of a new economy and society. Crops from the New World increased food production, commercial and manufacturing enterprises expanded, and with the coming of the Europeans via sea, new trading connections would be formed. Finally Christianity was reintroduced into China under the Jesuit Matteo Ricci.