The Japan–Ming trade-ship flag (日明貿易船旗, Nichi-Min bōeki sen-ki) is an object dating to 1584 preserved at the Yamaguchi Prefectural Archives that has been designated an Important Cultural Property of Japan due to its historical significance and the light it shines on trade and relations between Momoyama Japan and Ming China.
In 1371, in an attempt to prevent opponents joining forces with the wakō, the Hongwu Emperor, founder of the Ming, issued a maritime prohibition on private overseas voyages and commerce. Foreign merchants sailing to China for trade were also banned, communication with anyone defying this ban was punishable by death.[3][4] In 1383, a trade tally system was then introduced to facilitate tributary missions from foreign powers.[2]
The last of the Japanese missions to Tang China occurred in the ninth century, and several more recent attempts to establish diplomatic relations with the Ming had been rebuffed. But a Hakata merchant named Koitsumi (ja) returned from China and told Ashikaga Yoshimitsu of the profits that could be made through trade with the Great Ming. In Ōei 8 (1401), the Ashikaga shogunate dispatched the first of the Japanese missions to Ming China.[1][2][5] They carried with a "tribute" of gold, horses, and swords, as well as a number of Chinese castaways for repatriation. The mission was headed, like those that followed, by a Zen monk from the Five Mountains in Kyōto; Koitsumi served as vice-ambassador.[5] This mission "marked the re-opening of trade relations" between Muromachi Japan and Ming China.[1]
The second mission, headed by Kenchū Keimitsu, set off for China in 1403; when it returned the following year, it did so with an envoy from the Ming and 100 Yongle tallies: "this marks the beginning of the 'tally trade'" (勘合貿易, kangō bōeki),[5] the 1404 mission the first to implement this system.[1][5] While the Ming government would make official purchases, the Japanese envoys and accompanying merchants were permitted to conduct private trade with licensed counterparts. Ningbo was their assigned "port of entry".[3][6] For nearly one hundred and fifty years, until the last such mission in 1547, Chinese "gifts", such as silk thread, brocades, medicines, books, and ceramics, were provided in return for Japanese "tribute", such as lacquerware, bronze vessels, swords, armour, fans, screens, and sulphur (used in papermaking).[1][6][7]
Chinese copper coinage was also imported into Japan in vast quantities.[1][8] A 1999 study of 275 Japanese hoards, totaling 3,530,000 coins, found that the Chinese copper coins used in Japan in the Middle Ages were brought over in the largest number in the thirteenth century; in 1242 alone Japan is said to have imported one hundred million Chinese coins.[9] cf. Shinori hoard).[10][11] In 1407, the Ming court "gifted" its Japanese counterparts fifteen million coins, and thirty million more in 1434.[8] In the opposite direction, the 1539 Japanese mission took with it 180,000 kilograms (400,000 lb) of copper, close to twice as much as any of the fifteenth-century missions.[8] Discovery of rich veins of silver in Japan in the first half of the sixteenth century (see Iwami Ginzan Silver Mine) added this to the mix, and with the exchange rate between the silver tael and copper coins running at 1:750 in China and 1:250 in Japan, there was some profit potential.[3][8]