Kangofu was a tally or trading license issued by the Ming dynasty and used in trade, such as the Ming-Japanese trade, to confirm authorized tribute and trade ships between the Ming dynasty and a tributary state.
Kangofu were issued in about 50 countries in Southeast Asia. The main purposes of Kangofu were to clarify the position between a tributary state and the Ming dynasty (Sinocentrism) and to distinguish official ships from private ones.
The private ships in those days (partaking in private foreign trade) as typified by the wako (Japanese pirates) carried out trade in such a rough way that it caused a weakening of the Yuan dynasty which could not be overlooked. As the Ming dynasty required Japan (that is, the bakufu [Japanese feudal government headed by a shogun]) to crack down on the wako, the bakufu continued to trade using official ships and prohibited private foreign trade in the hope that they could exercise total control over existing profits from private foreign trade; thus, trade using Kangofu was implemented.
Both the Ming dynasty and the tributary state possessed kangofu and Kango teibo (matching seals on a sheet of paper divided into two: One was called Kangofu and the other called Kango teibo [registration book]). Between Japan and the Ming dynasty, Nichiji Kango or Nichijigo Kango (a tally or a trading license with the Japanese letter of nichi [日]) and Honji Kango (a tally or a trading license with the Japanese letter of hon [本]) were used; to trade, a Honji Kango (of which there were one hundred copies: Honji Nos.1 to 100) was brought by the Japanese envoy ship to the seaport in Ming (Ningbo), and compared with the Honji Kango teibo that the Ming dynasty possessed. The Japanese envoy ship dispatched to Ming China brought the Honjigo Kango in order from No.1, and they were compared with the Honji Kango teibo in the executive office in Zhejiang and the Ministry of Civil Administration in Beijing. Meanwhile, the Ming side brought the Nichiji Kango (of which there were one hundred copies: Nichiji Nos. 1 to 100) to Japan, and they were compared with the Nichiji Kango teibo that the Japanese side possessed.
The real Kangofu no longer exists, however, 'Boshi Nyuminki' (The Account of the Visit to Ming in 1468), the Zen priest Tenyo Seikei's travel report to Ming, includes an illustration of 'Honji Ichigo' (Honji No. 1).
Basically, the Kangofu was a long sheet of paper, large in size (82 cm long by 36 cm across), on which the matching seals with letters in red ink and handwritten Chinese kanji numbers (one of which was written in red ink) were printed, and on the other side of the document the type and number of articles for presentation, supplementary cargo, the number of passengers including the chief delegate were listed. Examples are as follows.
The no. 33 Kango of the matching seals with the Japanese letter of U (宇)'
The no. 35 Kango of the matching seals with the Japanese letter of U (宇)'
The no. 42 Kango of the matching seals with the Japanese letter of Jin (仁)'
The no. 74 Kangofu of the matching seals with the Japanese letter of Jin (仁)'
The no. 1 Kangofu of the matching seals with the Japanese letter of Gi (義)'
The no. 3 Kango of the matching seals with the Japanese letter of Chu (宙)'
The first Kangofu
In 1404, the Ming envoy sent by Emperor Yongle brought the Yongle Kangofu, on which the 'Seal of the King of Japan' was printed, to Yoshimitsu ASHIKAGA together with traditional Han Chinese clothing and a gold seal.