Idea of Unadon Occurred to a Man Who Wanted Warm Broiled Eels
Up to a certain time during the Edo period (1600 to 1867), eel cuisine simply meant kabayaki or broiled eels, which is made by dipping eels in sauce and broiling them on skewers. Broiled eels have a long history. It is said that they existed from as long as 350 years ago and it seems that they had even taken root among the common people of the Edo period.
Then, unadon (bowl of eel and rice) was added as another way of enjoying eels. It was born from a man’s desire for eating eels in a delicious way.
During the Bunka years (1804 to 1818), there was a theater in Edo, specifically in the area of present-day Nihonbashi Ningyocho, owned by a man by the name of Imasuke Okubo. This man began working as a houseboy and, due to his quick nature, finally became the owner. He liked eels. It is said that he often had a nearby eel restaurant Onoya deliver his meals.
When eel restaurants at that time made deliveries, they would first wrap heated rice bran in a bamboo sheath and place the eels on it to keep them warm during delivery. In spite of this, the eels would be cold by the time they arrived at the customer. And, when cold, half of the good flavor of the eels would be lost.
Thinking of how he could eat his eels hot, Imasuke one day suddenly hit upon the idea of placing the eels on or between hot rice. When Imasuke asked that the broiled eels be delivered on the rice, it was like killing two birds with one stone. The eels remained hot and the sauce also added flavor to the rice.
This unadon invented by Imasuke immediately became a sensation. The restaurant Onoya became the original house of unadon. Unadon spread so quickly that there was not a single eel restaurant in Edo that did not sell unadon.
Unadon first sold for around 100 to 200 mon, but after a while some restaurants began to sell it at around 60 mon. It seems that a heated price competition was going on.