Counterfeiting and Crackdowns on the Eiraku Tsūhō (永楽通宝) — The Most Widely Circulated and Most Counterfeited Coin

The Eiraku Tsūhō began to be cast during the reign of the Yongle Emperor (r. 1402–1424) of China's Ming dynasty. As its name indicates, the coin bears the Yongle era name, and it originally circulated within China. However, as Japan entered the Muromachi period, trade with Ming China became more active and large numbers of Eiraku Tsūhō were imported. Particularly from the latter half of the 1400s onward, around the time of Ashikaga Yoshimitsu (r. 1368–1394), the Eiraku Tsūhō had become one of the principal currencies in Japan. The coin's popularity in Japan rested first and foremost on its reliability and the abundance of its supply. As a result, the Eiraku Tsūhō came to be used widely in regional markets and among merchants, accepted as a trustworthy currency. Yet precisely because of its wide circulation, the Eiraku Tsūhō also became a target for counterfeiting. Inside Japan, numerous "Eiraku utsushi" were produced by melting down copper and casting it into molds, and counterfeit Eiraku Tsūhō began to appear on the market. In this era Japan's economy ran on coin currency, and the reliability of coins was crucial in commercial transactions. Because the circulation of counterfeit coins had an adverse effect on price stability, the daimyo and the shogunate were compelled to crack down on counterfeiting. Ashikaga Yoshimitsu, in 1405, ordered a crackdown on counterfeit coins and carried out their confiscation. In this way, the crackdown on Eiraku Tsūhō counterfeiting began at the same time as the counterfeiting itself.

Entering the 1500s, counterfeiting of the Eiraku Tsūhō became further organized and the techniques involved improved. Particularly during the Sengoku period, daimyo in various regions began casting their own Eiraku Tsūhō, which promoted the mass production of the so-called "Eiraku utsushi" counterfeit pieces. The manufacture of counterfeits employed casting techniques in which copper was melted and poured into molds. The molds were made based on genuine Eiraku Tsūhō and were crafted to resemble the originals as closely as possible, yet the finish remained crude in comparison to genuine coins. Counterfeit pieces were also generally lighter than genuine ones and often differed in color, which meant that knowledgeable individuals could tell them apart. Those involved in counterfeiting were local craftsmen and metalworkers. They applied their skills in an effort to produce counterfeits as close to the genuine article as possible, but the quality of the materials and the limits of their techniques meant that the inferior quality could not be denied. Counterfeiting of the Eiraku Tsūhō was carried out secretly in small regional workshops by the hands of such craftsmen. In the latter half of the 1500s, as powerful daimyo such as Oda Nobunaga (in power 1568–1582) and Toyotomi Hideyoshi (in power 1582–1598) proceeded to unify the country, control over currency was tightened. Wary of the adverse effects counterfeit coins had on the economy, Nobunaga and Hideyoshi strictly cracked down on the manufacture of counterfeit coins. As a result, the production of counterfeits gradually decreased but did not disappear entirely, continuing to be made in secret.

In the early 1600s, as the Edo period opened, the Eiraku Tsūhō was still in wide circulation within Japan. During this era, Tokugawa Ieyasu (r. 1603–1605) established the shogunate and tightened regulation of currency in order to stabilize the economy. In 1604 Ieyasu issued a currency recoinage order and thoroughly enforced crackdowns on counterfeit coins, yet even so counterfeit pieces were not completely eradicated and were in wide use particularly in rural areas. Behind the circulation of counterfeit coins lay the fact that the supply of coin currency was insufficient. In regional markets, even counterfeit coins had value if they could be used, and commoners had no choice but to accept them. The exchange rate between counterfeit and genuine coins varied by region and circumstance, but in many cases counterfeit coins are said to have been traded at roughly 60 to 70 percent of the value of genuine ones. For commoners, even counterfeit coins posed no problem as long as they could be exchanged for goods needed for daily life. The large volume of counterfeit coins in circulation sometimes made prices unstable, but commoners adapted to those conditions and managed their daily lives with ingenuity. During this era the circulation of counterfeit coins brought confusion to the economy, yet people nonetheless carried on with their everyday lives.

The problem of Eiraku Tsūhō counterfeiting exerted a major influence on Japan's later monetary system. The development of the monetary system after the onset of the Edo period in particular can be said to have emerged in part as a reflection on the counterfeiting of the Eiraku Tsūhō. The Edo shogunate sought to ensure a stable supply of currency and the reliability of its value by increasing the issuance of gold and silver coins and suppressing the circulation of counterfeit pieces. In particular, Tokugawa Hidetada (r. 1605–1623) and Tokugawa Iemitsu (r. 1623–1651), successors to Tokugawa Ieyasu, advanced reforms to the monetary system and strengthened the crackdown on counterfeit coins. Behind this lay the significant impact that Eiraku Tsūhō counterfeiting had had on the economy. Even today, the Eiraku Tsūhō continues to attract attention for its historical value. The existence of counterfeit pieces in particular provides clues to understanding the technology and economic conditions of the time, making them valuable resources from an archaeological standpoint as well. The problem of Eiraku Tsūhō counterfeiting continues to offer lessons for the modern age in considering the reliability of currency and economic stability.