Ban on direct trade between Japan and China

The ban on direct trade between Japan and China turns a political rupture into a commercial system: Chinese silk reaches Japan through Portuguese intermediaries, while Japanese silver pays for it, and the priests who can interpret between the countries become essential to the exchange. The arrangement enriches its middlemen and touches the lives of samurai, but Toranaga’s challenge to its prices reveals how dependence on trade can become a contest over power.

Background and Operation

The restriction rests on a long-standing state of hostility between China and Japan. China would permit no direct trade with Japan, even though Chinese silk was vital in Japan’s hot, humid summers and only a minuscule quantity of contraband cloth had previously reached the country, at enormous cost. The ban therefore did not end demand; it made access to the commodity scarce and politically controlled.

The arrangement changed when the Chinese emperor allowed the Portuguese a small permanent base at Macao and agreed to exchange silk for silver. Japan had silver in abundance, and the Portuguese occupied the crucial position between the Chinese supply and Japanese demand. The result was a flourishing trade that benefited both countries while making the Portuguese exceptionally wealthy. The prohibition on direct exchange thus reinforced, rather than removed, the importance of commerce: the goods crossed borders, but only through an authorized intermediary.

Intermediaries and Dependence

Portuguese commercial authority depended in part on the Jesuits. Their priests were among the few people able to speak both Chinese and Japanese, so they served as negotiators and interpreters as well as religious figures. As the trade expanded, their role became more indispensable. Japanese rulers who wished to preserve access to the exchange had reason to tolerate both the priests and the spread of their religion, despite resentment of foreign influence.

That dependence reached beyond court diplomacy. The yearly trade had become vast and touched the life of every samurai. It also supported a significant Christian presence: many important Christian daimyos and hundreds of thousands of converts lived in Japan, most of them in Kyushu, near the Portuguese port of Nagasaki. The prohibition therefore connected trade policy to domestic religious and political arrangements. Opposition to Portuguese privilege could threaten access to valued goods, while protecting the trade also meant accepting the presence and influence of the intermediaries who controlled it.

The broader maritime setting intensified this imbalance. Navigators lacked a reliable way to determine longitude, and rutters containing practical knowledge of routes, winds, currents, hazards, and ports were treated by Portugal and Spain as national secrets. Control of trade depended not only on the permission to carry goods but also on access to the information and ships that made long-distance passage possible. The ban on direct exchange formed part of a system in which commercial access and maritime knowledge were both unevenly distributed.

Toranaga’s Challenge to the Terms

Toranaga turns the monopoly into a subject of formal political scrutiny. He argues that the Portuguese charge for Chinese trade produces extraordinary profits because they overprice the silk they alone can obtain in China, while paying too little for the Japanese silver accepted in exchange. His complaint does not deny the prohibition on direct trade; it targets the unequal terms that the restriction allows the Portuguese to impose.

Rather than treating the matter as a private grievance, Toranaga asks the Portuguese to answer formally, in writing, and invites them to provide the Regents with a report on rates of exchange among silver, silk, and gold. The request brings the mechanics of the trade into political view: prices and exchange rates, usually controlled by intermediaries, become matters on which the rulers of Japan can demand an account. Ferriera calls the request arrogant, while Alvito recognizes that the Portuguese are already in trouble. The exchange exposes a conflict between the commercial privileges that sustain Portuguese power and the Japanese authority seeking to examine them.

Political Consequences and Significance

The prohibition gives the Portuguese leverage, but it also gives Japanese leaders a target. Because the intermediary system rests on Japanese permission and tolerance, its beneficiaries cannot assume that commercial privilege is politically secure. Toranaga’s demand uses that vulnerability to contest the terms of trade without claiming that the existing route can simply be bypassed.

The same entanglement appears in later negotiations over money and shipping. Alvito and the Jesuit leadership propose that Ferriera carry ten thousand ducats of Toranaga’s gold aboard the Black Ship to invest in India, with the Society helping place the funds through its usual sources. The proposed transaction illustrates how Portuguese shipping and commercial networks remain valuable even amid political friction: the contest concerns who controls the profits and on what terms, not merely whether exchange should occur.

The ban is therefore more than a barrier between two countries. It is the condition that makes a narrow group of translators, merchants, and sea powers necessary, allowing commercial intermediation to support both wealth and religious influence. Toranaga’s scrutiny of exchange rates reveals the structure beneath the apparent flow of goods: silk and silver circulate, but access, information, and profit remain concentrated in the hands of those authorized to connect them.