Kaisen

A model of a Ryukyuan tribute ship, on display at the Okinawa Prefectural Museum

• Other Names: 進貢船 (shinkou sen), 接貢船 (sekkou sen)
• Japanese: 楷船 (kaisen)

Kaisen were a type of Ryukyuan ship used to carry official missions to Kagoshima. They were typically ships that had previously been used to sail to China, as either shinkôsen ("tribute ships" carrying official Ryukyuan tribute missions to China) or sekkôsen (ships which went to bring Ryukyuan officials back from China, often transporting trade goods as well); after three or so such journeys to China, a ship would often be stripped of its weaponry, and thus transformed into a kaisen, to be used for journeys to Kagoshima.

Such ships were typically around thirty meters long and eight meters wide, with a main mast roughly thirty meters in height. They were of a nearly identical design to Chinese junks plying the same waters.

While shinkôsen carried official missions to China roughly once every other year, sekkôsen traveled to Fuzhou in the alternating years, ostensibly to bring the previous year's mission back home; however, both shinkôsen and sekkôsen also carried considerable amounts of tribute/trade goods, playing a vital role in the flow of silver, herbal medicines, a variety of luxury goods, and other products, between China, Ryûkyû, and Japan.

References

• "Sekkôsen," Okinawa Compact Encyclopedia, Ryukyu Shimpo, 1 March 2003.
• "Tribute Ship to China Model," gallery label, Okinawa Prefectural Museum.