Japanese Copper Across the Sea

Isolation from the Outside World

Europeans, and in particular the Portuguese and Spanish who experienced the reformation and the renaissance in the 16th century, first sailed to Japan as part of an effort to spread Catholicism by extending their trading activities around the globe. The Portuguese arrived in 1543, bringing guns to trade, while the Catholic missionary Francisco Xavier landed in 1549.
Then, in 1600, one ship from a five-ship East Asian expeditionary fleet that had sailed from Rotterdam, Holland, drifted ashore on the Japanese coast. The fact that this ship carried both Dutch and English sailors made its arrival a major foothold for the sailors' two Protestant countries to move into Japan.
However, the governing Tokugawa shogunate (1630-1867) disliked the antagonism between the Catholic and Protestant countries, as well as the discord among the foreigners over trade with Japan. The shogunate enacted and resolutely enforced a ban on Christianity which was at the center of new restrictions on trade, and further cut off exchanges with the outside by forbidding Japanese people from entering or leaving the country. Amazingly, these policies did not unravel for over 200 years, until the arrival of warships from the United States.

Exporter of Copper and Silver

However, Japan did not choose total isolation during this period. There were restrictions, but there was also trade with Holland, China, the Ryukyu Kingdom (now Okinawa Prefecture, but an independent kingdom into the latter half of the 19th century), and Korea.
Japan's main imports in the second half of the 17th century were raw silk and silk goods, medicines, and spices. Goods like copper, camphor, pottery, and marine products were exported to pay for them.
Today more than ever, Japan relies on a wide range of imported natural resources, including coal, crude oil, and iron ore; but from the mid-16th century to the beginning of the 17th, Japan was a resource-rich country-to the extent that silver, and then copper, were its principal exports. Although it varied from year to year, Japan's total copper output from the end of the 17th century to the beginning of the 18th was around 6,000tons/year-the highest in the world at the time. Copper accounted for 60-70% of Japanese exports, and it was loaded onto ships at Japan's only international trading port, Dejima in Nagasaki Harvor. From there, copper was transported to China, Southeast Asia, and India, not to mention distant Europe. In the first half of the 1670s, the volume of Japanese copper exported to Europe reached between one-third and one-half the output of Sweden, Europe's major producer of the day. This had a significant impact on the European copper exported at that time was supplied by Sumitomo.

Contributing to the Wealth of the Nation

In the last issue, we explained how Soga Riemon (1572-1636), one of the founders of the Sumitomo Group, hit on a refining process called nanban-buki for better separating silver from copper, and that his son Tomomochi (1607-1662) passed this technique on to his peers in the copper trade in Osaka.
After that, the technique caught the attention of the shogunata, which decreed that domestically produced copper that had not been refined in Osaka using nanban-buki could not be exported. As a result, Osaka prospered as a major locus of copper refining. By establishing the nanban-buki technique and supporting other in the trade, Sumitomo became a leader in Osaka copper refining and made a major contribution to the wealth of the nation by spurring copper exports and stemming the outflow of silver from Japan. The shogunate subsequently enacted a variety of copper export policies designed to ensure an ample supply of copper for export, including the establishment of mechanisms to tighten control over the storage, smelting, and sale of copper, and Sumitomo-as Japan's largest copper smelter-displayed its leadership in fulfilling a role in the execution of these national policies.
Building on its copper export business, Sumitomo expanded into importing raw silk, silk goods, and other products. These moves allowed it to accumulate the wealth needed for embarking on the full-scale operation of mineral mining as well.