The importance of sweet potatoes in the history of Japan

Jul 2018
497
Hong Kong
#1
Source : 青木昆陽「蕃藷考」が江戸時代の民を救う~サツマイモが吉宗に奨励された理由

On 9th March 1735, a semi-ronin Aoki Konyo (青木昆陽) presented his proposal Sweet Potatoes Investigation (蕃藷考) to the 8th Tokugawa Shogun Yoshimune (徳川吉宗). The Shogun was impressed and made a historic decision — he ordered the mass-cultivation of sweet potatoes in the Kanto Region (関東) of Japan. This was a turning point in the agricultural history of Japan, which no longer merely relied on rice as her only staple agricultural crop.

How this dramatical change occurred ? Who is Aoki Konyo ? What was the cause of the Shogun's decision ? How was the Japanese beneficial of that ? I'll make a short narration and analyze at below served for this topic's background story.

The origin of sweet potatoes and how did her spread to Japan

Around 10,000 - 8,000 BC, the origin and domestication of sweet potatoes occurred in Central and Southern America. In the 15th century, a seafarer-adventurer Columbus brought sweet potatoes from the America to Europe. Later the European spreaded this new crop to China through maritime activities via the Philippines, and soon transmitted to the peripheral areas of Japan such as the Miyako Island (宮古島), the Okinawa Island (沖縄本島) and the Tanega Island (種子島). In the Miyako Island, there're several places found where sweet potatoes were used for sacrifice in ritual worship.

By the Edo Period, the first lord of the Satsuma Domain (薩摩藩) Shimazu Iehisa (島津家久) commenced the Invasion of Ryukyu (琉球侵攻), thus he introducted sweet potatoes into Satsuma by bringing prototypes back from the conquered region. Later the Portuguese also introduced this crop. Therefore, the Satsuma inhabitants began to cultivate it. Gradually, the western Japan including the large city of Miyazaki (宮崎), Nagasaki (長崎) and Kyoto (京都) was influenced by the introduction of sweet potatoes. Around that time, Shogun Tokugawa Yoshimune recognized sweet potatoes' value in the times of major crop failure.

Why the Shogun decided to promote the cultivation of sweet potatoes ?

The Kyoho Famine (享保の大飢饉, occurred in AD 1732-33) taught Yoshimune a painful lesson that over-reliance on rice as stable crop cultivation proved disastrous — the other staple crop had to be founded for increasing the diversity of food production. Under this background, the Sweet Potatoes Investigation done by Aoki Konyo had a significant impact on the mind of the Shogun.

In comparison with other agricultural crops, sweet potatoes is easy to be cultivated and even growable on the infertile soil. It comprises plenty of calcium, Vitamin C and dietary fibre, thus possesses the high nutritional value. Undoubtly, it is an ideal mass-cultivated crop for relieving the scarcity of food during the times of major crop failure of paddy field.

Normally, a low-status person like Aoki Konyo should never have any chance to meet with the Shogun. But thanks to his acquaintance with some prominent Shogunate magistrates such like Ooka Tadasuke (大岡忠相), he was able to deliver his insightful proposal to the Shogun. His proposal did exactly what the Shogun Yoshimune wanted, so Yoshimune instantly ordered this new agricultural crop mass-cultivated in the Kanto Region as experiment — Konyo was instructed to cultivate sweet potatoes in the Koishikawa Botanical Garden (小石川御薬園, nowadays close to Makuhari, Chiba Prefecture 千葉県幕張), and he succeeded after a year of cultivation. Hence, he formally became the Shogunate's retainer and was subordinate to Tadasuke. It was a remarkable success in his career !

Hereafter, Konyo was given the privilege of freely conducting the investigation of old documents of the Shogunate, and thus acquired the Dutch. By this linguistic ability, he was even able to translate the Dutch works for further increasing his knowledge.

Aoki Konyo was popularly reputed "Mr. Sweet Potato" (甘藷先生) by folks as his reputation grew among the Japanese. In the supposed experimental place (for cultivation) of Makuhari, Chiba Prefecture, there was a temple named Konyo Shrine (昆陽神社) specifically erected for enshring the "Mr. Sweet Potato" as a deity who made a huge contribution in alleviating the famine.

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So what do you think about the aforementioned story ? You could even share the history of sweet potatoes in other regions and eras for making comparisons and let us have better understanding and wider scope about the development and impact of this agricultural crop. So, any opinion or feedback ?
 
Oct 2016
1,137
Merryland
#4
the sweet potato could be cooked without much processing, as opposed to the threshing etc for rice.
sweet potatoes (in the ground) were less likely to be burned or taken by invaders or raiders.
very nutritious. WWII and postwar Japan benefited greatly from them.

not to be confused with the yam, which is much starchier. anyone in North America that thinks they've eaten yams has almost certainly had sweet 'taters instead.
 
Jul 2018
497
Hong Kong
#5
the sweet potato could be cooked without much processing, as opposed to the threshing etc for rice.
sweet potatoes (in the ground) were less likely to be burned or taken by invaders or raiders.
very nutritious. WWII and postwar Japan benefited greatly from them.

not to be confused with the yam, which is much starchier. anyone in North America that thinks they've eaten yams has almost certainly had sweet 'taters instead.
Interesting, the sweet potato seems more valuable than I thought.
 
Oct 2016
1,137
Merryland
#6
white ('Irish') potatoes were popular for the same reason; a frozen field of tubers was a food bank for the natives. outside troops rarely took the time/trouble to dig them.

I like them in pies, but also micro-waved with an added pat of butter.
 
Oct 2014
77
Osaka
#7
The potato entered Japan as a western innovation, but it has existed for centuries by now. Although it didn't really get popular until the Meiji era. It used to be associated a bit with western cuisine but that isn't necessarily true any more these days as you can get it in washoku type dishes, the nikujaga is one but there are others. Throw in some sake and pepper powder and a few other things and you've got a pretty good Japanese dish.

The storied history of the potato in Japanese cooking | The Japan Times