The Coin on the Day the Rice Vanished
When famine swept the land, the single coin that sustained daily life reverted to mere metal. Amid rice riots, policymakers offered different answers. It was a question of circulation versus accumulation.

A Life Sustained by a Single Coin
In 1636, the minting of a new coin began in Edo and Ōmi Sakamoto. It was the first domestically produced coin in 678 years, since the Kengen Taihō. Called the Kan'ei Tsūhō, this coin would support the lives of the common people for over two hundred years. It had a diameter of two and a half centimeters and a weight of about one monme. With this single coin, people bought rice and obtained their daily sustenance.
However, the day came when the value of that coin wavered. In 1785, one hundred mon could buy one shō and one gō of white rice in Edo. Two years later, at the beginning of May 1787, that amount fell to four gō and five shaku, and by the seventeenth of the month, it was down to three gō. The amount of rice that could be bought for one hundred mon had dropped to less than a third of its former value.
Destroy, But Do Not Steal
The color of the sky began to change in 1782. The following year, Mount Iwaki and Mount Asama erupted, and dust from the eruption of the Laki volcano in Iceland covered the northern hemisphere. The sunlight weakened, and the rice crops failed. In the Hirosaki domain, over 102,000 people starved to death, and in the Morioka domain, the number exceeded 75,000, roughly a quarter of the domain's population.
On the night of May 20, 1787, a rice merchant's shop was destroyed in Akasaka, Edo. The next day, these uchikowashi, or destructive riots, spread throughout the city. The targets were rice merchants, rice polishers, pawnbrokers, and purveyors to the shogunate. However, shops that continued to sell rice despite the price hikes and households that helped neighbors in need were spared. They destroyed but did not steal, and they did not set fires. There was a code of conduct.
Prior to this, a famine had also struck the western provinces in 1732. Insects swarmed the rice plants, and the harvest fell to about a quarter of a normal year. The shogunate's official tally of starvation deaths was 12,172, but the Tokugawa Jikki records the number as 969,900. The death toll for the same famine differs by a factor of eighty. At that time as well, the price of rice doubled, and the first uchikowashi occurred in Edo.
The Man Called the 'World-Rectifying Great Deity'
To cease relying solely on the annual rice tax for revenue and instead collect taxes broadly and thinly from commerce and finance—this was the paradigm shift that Tanuma Okitsugu attempted. He officially recognized the kabunakama (trade guilds) and had them pay unjōkin and myōgakin fees, established monopolies on copper and Korean ginseng, and issued the Nanryō Nishu-gin silver coin.
In 1784, inside Edo Castle, the Junior Councilor Tanuma Okitomo was slashed by a hatamoto, Sano Masakoto. Okitomo died eight days later, and Sano committed seppuku. It was said that the high price of rice then fell, and the people began to call Sano the Yonaoshi Daimyōjin, or 'World-Rectifying Great Deity.' There was no connection between the assault and the price of rice. The experience alone of the price drop transformed a man into a god. The man who tried to shift from a rice-based to a money-based tax system bore the blame for the high price of rice.
Circulation or Accumulation?
What Matsudaira Sadanobu, who became Senior Councilor after Tanuma, did was to enforce accumulation. He had the daimyō and hatamoto set aside fifty koku of unhulled rice for every ten thousand koku of their domain's yield. In 1791, he made each town in Edo cut its municipal expenses and set aside seventy percent of the savings. This was the Shichibu Tsumikin, or Seven-Tenths Reserve Fund.
The Edo Town Assembly Hall was entrusted with this money and rice. The goal was to store enough to feed 500,000 Edo townspeople for one month. The story that not a single person starved to death in Sadanobu's home domain of Shirakawa is a legend. Nevertheless, this reserve system alone continued for about eighty years, until the beginning of the Meiji era. A payout came forty-five years later, during the Tenpō famine.
Tanuma tried to circulate money, while Sadanobu had it accumulated. The one that proved effective against famine was accumulation. By 1874, this reserve fund, combining money, rice, and land, was worth 1,430,000 ryō.
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