Ningbo Incident

The Ningbo Incident (Chinese: 寧波之亂; Japanese: 寧波の乱) was a 1523 brawl between trade representatives of two Japanese daimyo clans — the Ōuchi and the Hosokawa — in the Ming Chinese city of Ningbo. The Ōuchi pillaged and harmed local residents, causing massive damage. The turmoil resulted in the interruption of the Ming-Japanese trade and led to a surge in piratical (wokou) activity on the Chinese coast. The episode is also known by the names Ningbo Tribute Conflict (寧波争貢事件), Mingzhou Incident (明州之亂), or the Sōsetsu Incident (宗設之亂).

Ming China considered Japan a tributary state in its Sinocentric world order. Under the Ming tributary system, Japan could present tribute to the Chinese imperial court and be rewarded in the form of gifts by the emperor. This was essentially an exchange of Japanese products for Chinese goods, and, being the only legal form of trade between China and Japan during the Ming's maritime prohibitions, was extremely profitable. The Japanese were assigned the city of Ningbo as their port of entry into China, and only those with tallies granted by the emperor were officially allowed to travel and trade within the boundaries of China. Hence, the Ming-Japan trade was called the "tally trade" (勘合貿易, kangō bōeki in Japanese and kānhé màoyì in Chinese).

The handling of the tally trade on the Japanese side was the responsibility of the "King of Japan", as the Chinese called the Ashikaga shogun. However, after the Ōnin War broke out in Japan in 1467, the Ashikaga shoguns were reduced to such powerlessness that control of the lucrative China trade became contested between the nominal Ashikaga vassals the Hosokawa clan in Kyoto and the Ōuchi clan of Yamaguchi.

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