Chōsen Tsūhō — The Mission of the Imported Coin that Filled 600 Years of Coin Blank in Japan

In the 6th year of Tengyō (943), the last of the Imperial Coins, the Ken'en Taibō, was issued in Japan. For about 600 years since then, Japan lacked its own official currency, a 'coin blank period'. This does not mean economic activities halted. Trade from the late Heian to Kamakura and Muromachi periods expanded, relying entirely on coins imported from China and Korea.

From the late Heian to Kamakura period, trade with Song China was thriving, resulting in massive inflows of Song coins (the main subject of imported coins). Song coins settled in the Japanese market as 'one-mon coins' and were used for rice price conversions. However, after Song was defeated by Yuan (1271-), the import routes changed. From the 14th to 15th centuries, Yongle Tongbao (minted in 1408), issued by Ming (1368-1644), became the main imported coin, with massive imports through Japan-Ming trade (Tributary Trade, from 1401).

Amid this backdrop, the Chōsen Tsūhō was coined in the 5th year of King Sejong of Joseon (1423). The Joseon dynasty, founded by overthrowing Goryeo in 1392, began this under its fourth king. Sejong's reign (1418-1450) is known for the 'creation of Hangul' (1443) and was a cultural golden age, with currency system establishment being part of it.

Initially coined for distribution within Korea, Chōsen Tsūhō entered the Japanese market through active trade (primarily via Hakata and Tsushima) between Korea and Japan. Alongside Yongle Tongbao as a 'reliable foreign coin', Chōsen Tsūhō played an essential role in the commercial activities during the Muromachi period in Japan. Confirm the flow from Imperial Coins to imported coin eras in Overall Picture of Ancient Coins.

During the Muromachi period, local daimyo also issued 'Senzenrei', trying to eliminate excessively worn or clearly inferior coins, which indicates the wide variety of imported coins circulating at the time.

During the Muromachi period (1336-1573), Japanese commerce significantly advanced. Amid political instability from conflicts like the Ōnin War (1467-1477), regional autonomy progressed, leading to the establishment of markets nationwide—regular markets, free markets, temple-front markets—spurring product distribution. The indispensable medium for these commercial activities was imported coins, of which Chōsen Tsūhō was a part.

Hakata was a critical point for Korea-Japan trade. The Sō clan of Tsushima mediated diplomacy and trade with Korea, bringing Korean coins, silk, and ceramics to Japan. Hakata merchants made huge profits reselling these inland. Chōsen Tsūhō circulated in big cities like Kyoto, Sakai, Nara, gaining acceptance as a 'reliable foreign coin.'

Documentary evidence on the usage differences between Yongle Tongbao and Chōsen Tsūhō is limited, but differences are presumed based on region and transaction type. Yongle Tongbao was mainly used for China trade settlements or large-scale business, whereas Chōsen Tsūhō was broadly used in Korea trade and local daily transactions.

Entering the Sengoku period (around 1467-1590), warlords intervened directly in currency policies. For instance, Takeda Shingen of Kai prohibited what he deemed 'bad coins' from circulation, whereas certain foreign coins were endorsed as 'good coins'. Within such policies, both Yongle Tongbao and Chōsen Tsūhō were often treated as good coins, continuing as reliable distribution means.

Yet, bartering (rice, cloth, soybeans, etc.) remained mainstream in rural areas where coin economies were not fully ingrained. The circulation of imported coins was concentrated around urban and main trade routes. Nevertheless, with commercial growth, their range gradually expanded, becoming common in large rural markets by the late Sengoku period, as confirmed in Explanations of Anazen and Imported Coins.

In the 18th year of Tenshō (1590), with his unification of Japan, Toyotomi Hideyoshi entered a new stage in currency policy. Hideyoshi aimed to organize a gold and silver currency system through issuing gold coins (Tenshō Ōban, Tenshō Tsūhō). However, imported coins continued to dominate the market in terms of copper coins.

After Tokugawa Ieyasu established the Edo Shogunate in Keichō 8 (1603), the shogunate sought national currency system unification. Gold coins such as Keichō Koban and Keichō Ichibugin, and silver coins like Keichō Chōgin were organized from Keichō 6 (1601). For copper coins, it took time until the full-scale nationwide minting of Kan'ei Tsūhō.

The history of Kan'ei Tsūhō is complex. The name 'Kan'ei Tsūhō' saw its first minting as unauthorized (privately minted) coins in Mito in Kan'ei 3 (1626). Later, full-blown official minting began with bakufu approval in Kan'ei 13 (1636), manufactured at minting sites nationwide. From this point, imported coins rapidly withdrew from the market.

The Edo Shogunate gradually strengthened the policy of 'using Japanese domestic coins.' Laws restricting imported coin circulation were issued, and Kan'ei Tsūhō became the main character of coins in the market. Legal provisions allowed continued use for some time, but the overwhelming supply of new Kan'ei Tsūhō quickly overshadowed the presence of coins like Chōsen Tsūhō or Yongle Tongbao, as observed in Details of Kan'ei Tsūhō.

In about half a century from Kan'ei 13 (1636), Chōsen Tsūhō disappeared from the Japanese market's main stage. The era of imported coins that supported Japanese commerce for over 200 years thus came to an end. Nonetheless, their legacy quietly carried forward into the Edo period's monetary economy as the foundation of Japan's coin culture.

What is the evaluation of Chōsen Tsūhō in today's ancient coin market? Pricewise, the typical range is from a few thousand to tens of thousands of yen, depending on condition, minting time, and acquisition route. Well-preserved and fine coins (those with clear characters and little wear) can fetch over tens of thousands of yen. Among imported coins, alongside Song coins (Chinese Song coins) and Yongle Tongbao, it is well-known and collected by a wide range of enthusiasts from novice to advanced collectors.

From an authenticity assessment standpoint, Chōsen Tsūhō is relatively straightforward but there are later replicas. The consistency of characters, quality of copper, shape of the square hole, and weight are key points for authenticity. Differences in wear and copper alloy composition exist between Chōsen Tsūhō circulated in Japan and those used in Korea (an area of ongoing research). Having Basic Knowledge of Coin Auctions and Guidelines of Coin Grading is the premise for safe trading.

Historically, collecting Chōsen Tsūhō means feeling the historical Japan-Korea economic exchange in one's hand. Held by Muromachi Hakata merchants, used in Sengoku markets, replaced by Kan'ei Tsūhō in early Edo—its historical weight is condensed in a single coin.

Moreover, for those collectors systematically collecting imported coins, Chōsen Tsūhō serves as a 'complementary entity for Japan's coin blank period', essential for the collection. For tracing coinage history through Imperial Coins, Imported Coins, Kan'ei Tsūhō, it represents the middle period. Check present value at Market Index for purchase reference.

The period when Chōsen Tsūhō circulated in Japan, from the Muromachi to early Edo, corresponds to around 200 years, roughly from King Sejong’s 5th year in Joseon (1423) to around Kan'ei 13 (1636). During these 200 years, Japan's coin economy couldn't exist without imported coins. Chōsen Tsūhō, telling this story, quietly yet eloquently continues to narrate the history of Japan-Korea economic exchange today.