The Tsushima Domain and the Chōsen Tsūshinshi — The Japan-Korea Diplomatic and Trade Route Forged by Swords

What Kind of Domain Was the Tsushima Domain? — Geography and Its Role as Gateway to Korean Diplomacy

Tsushima is an island situated roughly midway between Kyushu and the Korean Peninsula, and throughout the Edo period it was the domain of the Sō clan. The terrain was mountainous with little arable land, and the domain's finances could not be sustained on rice harvests alone; the Sō clan had long relied on trade with the Korean Peninsula to sustain the domain's livelihood. These geographical conditions were precisely what made the Tsushima domain the sole gateway for the Edo shogunate's diplomacy and trade with Korea.

When discussing the history of swords, attention tends to focus on domestic production centers such as Kyoto, Kamakura, and Bizen, and on tales of battle; yet during the Edo period, nihontō were also connected to the Korean Peninsula via the Tsushima domain. Understanding the reality of these external exchanges provides a key to seeing nihontō not merely as a self-contained domestic craft object, but as a commodity embedded in the diplomatic and trade networks of East Asia.

Restoration of Diplomatic Relations in the Keichō and Genna Eras — The Kiyū Yakujō and the Role of the Tsushima Domain

Toyotomi Hideyoshi's Bunroku-Keichō campaigns (1592–1598) severely damaged relations between Japan and Korea. Diplomatic ties between the two countries were effectively severed, and the Tsushima domain's trade revenues suffered a severe blow.

When Tokugawa Ieyasu took power, Sō Yoshitoshi, lord of the Tsushima domain, repeatedly negotiated with the Korean side toward the restoration of diplomatic relations. As a result, in Keichō 14 (1609), the Kiyū Yakujō was concluded, and the Tsushima domain obtained the privilege of resuming trade with Korea. This treaty institutionally established the Tsushima domain's status as the "gateway" standing between the Edo shogunate and the Joseon dynasty.

The Chōsen Tsūshinshi — The Diplomatic Delegations That Visited Japan During the Edo Period

Following the normalization of relations under the Kiyū Yakujō, the Joseon dynasty came to dispatch official diplomatic delegations known as the Chōsen Tsūshinshi to Japan at important occasions such as a change in shogun. Between 1607 and 1811, the Tsūshinshi visited Japan on multiple occasions, traveling in grand processions all the way to Edo.

The Tsushima domain took sole charge of guiding, guarding, and interpreting for the Tsūshinshi on their visits to Japan. The Sō clan kept retainers fluent in Korean from generation to generation, and the Tsushima domain handled the practical work of exchanging diplomatic documents and arranging ceremonial proceedings. The journey of the Tsūshinshi delegation to Edo was a major event for the domains along their route as well, and served as an opportunity for encounters with Korean culture within Japan. Note that the final mission of 1811 was changed to a format known as Ekichi Heinrei, in which the envoys were received not in Edo but in Tsushima, due in part to the Edo shogunate's financial circumstances.

Wakan Trade — The Japanese Settlement in Busan and the Export of Swords

The base of the Tsushima domain's practical trading operations was the Wakan, a Japanese settlement established on the Korean side in Busan. Tsushima domain samurai and merchants resided permanently in the Wakan, conducting both official and unofficial trade while dealing with Korea's liaison institutions.

In this trade, copper and craft goods processed within Japan were brought in from the Japanese side, while cotton, Korean ginseng, and the Daizōkyō were among the goods brought to Japan from the Korean side. Swords and tōsōgu were likewise handled as items of trade through the Wakan, and it is known that they formed part of the flow of goods between Japan and Korea via the Tsushima domain. The fact that Edo-period nihontō were connected not only to the domestic market but also to such external trade routes is an aspect that tends to be overlooked when considering the distribution history of nihontō.

The Diplomatic Ceremonial Role of Swords — Tachi as Formal Gifts

In Japan's warrior society, the practice of using tachi as formal gifts — known as shinmotsu — had long been established. A prime example is the tachi mokuroku custom, in which a tachi is presented together with an inventory document on ceremonial occasions of gift exchange between shogun and daimyo.

Records show that in the Japan-Korea diplomatic settings handled by the Tsushima domain as well, swords were presented as gifts as an extension of such warrior-society protocol. However, much of the specific detail — which tachi was presented on which mission — requires verification from historical sources; what this article wishes to establish is that there existed in Edo-period Japan a cultural foundation in which swords were treated as part of official diplomatic ceremony.

The Japan-Korea relationship mediated by the Tsushima domain can be summarized as consisting of the following elements.

• Diplomacy: normalization of relations under the Kiyū Yakujō (1609) and visits to Japan by the Chōsen Tsūshinshi totaling more than ten missions
• Administration: interpretation, escort, and guarding by the Tsushima domain, and the cultivation of Korean-language personnel from generation to generation
• Trade: exchange of copper, cotton, Korean ginseng, swords, and other goods centered on the Wakan in Busan
• Ceremony: the positioning of swords as part of gift-giving protocol, typified by the tachi mokuroku

The Significance of the Tsushima Route from a Modern Perspective

The Japan-Korea diplomatic and trade route of the Tsushima domain demonstrates that nihontō were not craft objects that existed solely within Japan throughout the Edo period, but were also trade goods embedded in the international relations of East Asia. When appreciating or collecting swords, knowing the background of each individual blade — in what era and in what distribution network it was made and used — leads not only to an appreciation of its value as an object but also to the pleasure of savoring its historical depth.

If you browse the listed works with an interest in the historical background that swords have traveled through, you should find yourself appreciating the value of each blade from a perspective you have not had before.