Erizenirei was a ban on the erizeni act (the act of accepting only high-quality coins) enforced by the Muromachi bakufu (Japanese feudal government headed by a shogun) or daimyo (feudal lords) in the Muromachi period.
Around the Muromachi period, increasingly more money became circulated corresponding to progress in commodity economy, and use of money for paying taxes was promoted. Ming currencies in addition to the Sung currencies that had already been in use became used additionally. As demands for these currencies increased, Shichusen (coins made privately) and low-quality Torai-sen (coins imported from China) became circulated. Therefore, the general public hated low-quality coins and sometimes carried out erizen acts in transactions, hampering smooth circulation of currencies.
The process of its promulgation and the effects
Therefore, the Muromachi bakufu and many daimyo promulgated Erizenirei many times, specifying a mixing ratio of low-quality currencies to high-quality currencies or forcing to circulate currencies in the condition that the circulation of certain low-quality currencies should be prohibited. However, since the control was local and many of the general public wanted to eliminate Bitasen (low-quality coins whose surfaces were worn away), the results were not satisfactory. Nobunaga ODA severely punished the persons who carried out erizeni acts. Later, however, Nobunaga changed the policy and specified an exchange ratio of low-quality coins to high-quality coins.
In the past, it was understood that Erizenirei was used to eliminate the erizeni act itself. However, Erizenirei then became that only a bad law to force the general public to use the low-quality Torai-sen, lots of which were held by the Muromachi bakufu and others. Rather, the following opinion has been gaining strength today: The erizeni act was restricted actually, but more attention should be paid to the aspect that certain erizeni acts were 'officially permitted,' for example, through the use of a mixing ratio or of an exchanging ratio. This is because some local daimyo who held no Torai-sen were more likely to permit erizeni acts officially to eliminate low-quality coins form their territories.
If a person obtained lots of high-quality coins from a daimyo who prohibited erizen, melt them and generated corresponding low-quality coins, the person could gain a huge profit. If such a situation occurred, the daimyo himself would have suffered a big loss and a serious inflation might also have ensued, through promoting the generation of low-quality false coins. However, the reason why such a situation did not occur actually was that the parties responsible for circulating low-quality Torai-sen were the Muromachi bakufu and influential families in the central government, explicitly showing that Torai-sen were at the center of the low-quality coins. "Ouchi-shi Okitegaki" (collections of laws and regulations established by the Ouchi clan), a bunkokuho (the law individual Sengoku daimyo (Japanese territorial lord in the Sengoku period) enforced in their own territories) of a Sengoku daimyo who promoted oversea trade actively, includes the following rather selfish description: The erizeni act shall be carried out for the coins paid as taxes but it is not permitted for the general public to carry out the erizeni act.
In the Yuan Dynasty and Ming Dynasty, the credibility of copper coins had been degraded, and the influential families and the merchants engaging in large-scale trade who monopolized oversea trade could get these coins by selling inexpensive things and quite easily. In trade with China, transactions of using a unit of 100 million coins were not unusual at that time. Therefore, even if erizen acts were carried out and coins like 'Kobusen' (copper coins cast from 1368 to 1398) were discriminated, little loss would be inflicted. Even the following instance occurred actually: Some persons in a position where false coins in the Ming Dynasty or Japan, for examples, Sakai-sen (coins cast in Sakai in the late 16th century) could be gathered and made into those coins possessed by other persons intentionally. The fact that erizeni acts were carried out and were officially permitted, even though some restrictions were imposed, impacted the credibility of the money economy in China greatly.