Cheng Shun-kung (Tei Shunko) (鄭舜功)

Cheng Shun-kung (鄭舜功, Tei Shunko; dates unknown) was an adventurer during the latter half of the Ming period in China. He came from Xin'an County, Guangdong Sheng, China.

Summary
During the Kangzi period (1521 - 1566) during the Ming dynasty, wako (Japanese pirates) repeatedly raided China's coasts. Chinese, represented by Wang Zhi (王直), accounted for a large part of wako in those days, many of whom made their headquarters on the coasts of the Goto Islands and Hirado of Japan to escape the crackdown by Ming. In those days, since Japan was in the midst of the Sengoku period (warring states period), they did not establish a system of arresting wako. The governor of Zhejiang 楊宜 dispatched an envoy to Japan, and asked Japan to arrest wako, while trying to gather intelligence of Japan's actual circumstances. It was Cheng Shun-kung who was selected as the envoy.

In 1556, Cheng Shun-kung came over to Japan through ryukyu and entered Bungo Province, where he was arrested by the Otomo clan, the ruler of the province in those days, and confined in Ryuho-an of Kaizo-ji Temple, Usuki City. During the next year, a subject of Cheng Shun-kung went to Kyoto with an envoy of the Otomo clan, and was allowed to request the Muromachi bakufu to suppress wako -- On the other hand, Cheng Shun-kung was still confined in Bungo Province, but allowed to gather intelligence of Japan's actual circumstances.

When Cheng Shun-kung returned to Ningpo, China together with an envoy monk of the Otomo clan, 楊宜 had already lost his position by 趙文華 and 胡宗憲 -- On the contrary, Cheng Shun-kung was arrested and exiled to Sichuan and imprisoned there for seven years.
At the end of the Kangzi period, Cheng Shun-kung wrote his experiences in Japan and Japan's actual circumstances in "Nihon Ikkan" (Japan One Model.)