Hyakki Yagyō Was a Day You Stayed Indoors

Not the Scroll

The night parade of a hundred demons is known today as a picture: a horizontal scroll, a column of animate objects and horned figures moving left to right, endlessly reproduced.

This note is not about the scroll. The history of those paintings — which is a real and well-studied subject — is outside what could be verified here, and nothing about their dating or lineage is asserted below.

What can be set out is what the phrase was doing in writing before the pictures, and it turns out to have been doing three quite specific jobs. It was a category a witness reached for. It was a set of dates. And in one case it was an address.

One Horse-Headed Oni

The passage that shows the first job is in the Uji shūi monogatari, the collection of tales assembled in the early thirteenth century.

It is the middle of the night. Wind is blowing and rain is falling and the weather is foul. Something is going along the main street chanting shogyō mujō — all things are impermanent, the opening of the Buddhist verse on transience.

The witness looks. It is as tall as the eaves, and it has the head of a horse.

And then comes the sentence that matters. He thinks: perhaps this is the hyakki yagyō — and he is terrified.

He sees one creature and names a category. There is no procession on the page. There is a single horse-headed figure in the rain, reciting scripture, and a man who has a phrase available for what to call this and applies it. The phrase is not a description of what he saw; it is the thing he decided he was seeing.

That is a very different object from a painted parade, and it is the earlier of the two.

A Day in the Calendar

The second job is the one that has vanished most completely from the popular account.

The historical synthesis in which these passages are collected observes that the night parade appears to have been limited to particular days — and it points, in a note, to records in the Uji shūi monogatari and in a Heian handbook of court miscellany which set out the danger to anyone who violates the yakō-imi: the prohibition on going out at night.

This was not a creature you might meet. It was a date on which you did not leave the house. The belief had a calendar, and the calendar had consequences attached for people who ignored it, and the consequences were written down in a reference work rather than a ghost story.

That single fact reorganises the subject. A monster is something that happens to you. A prohibited date is something you plan around — you do not travel, you do not call on anyone, you tell the household. It belongs with the other avoidances of the Heian year rather than with the bestiary, and it was observed by people who had no expectation of seeing anything at all.

The Historian Immediately Qualifies It

Here the source does something that deserves to be copied rather than smoothed over.

Having established the fixed days, the writer turns straight round and says: but it cannot be put only like that. And he gives the counter-case.

A practitioner at a temple in the province of Tsu meets the thing with no reference to any date at all. So the rule existed and the rule was broken by the evidence, and the man assembling the evidence printed both halves in the same paragraph.

I have read a good deal of writing on this subject and that paragraph is better than most of it. The popular version has a fixed answer; the source has a rule and a documented exception and declines to choose.

There Was an Address

The third job is the strangest, and it is in the notes rather than the text.

Places where such things were thought to appear had names, and they were used as names. One was the Onidono — the demon hall — and the Kishō, the demon place. These occur as ordinary proper nouns: in a tale of the twelfth-century collection Konjaku monogatarishū, which refers to the demon hall at Sanjō Higashi-no-Tōin; and in the diary of a court official, under a dated entry in the eleventh century.

A courtier wrote the name of a haunted building into his diary the way one writes any address. This is not a palace of demons in a story. It is a location in the capital, at a crossing that can still be found on a map, which people of the period called that.

Our note on what a yōkai is deals with how loosely these words were used; here the usage is at its sharpest, because the word doing the work in an official’s diary is oni.

The Man Under the Floor

The counter-case itself is worth telling, because it is nothing like the parade.

A practitioner is at a temple in Tsu. He hides and recites the spell of Fudō, the immovable one. A hundred or so creatures come crowding in.

And they do not attack him. They say: a new Fudō is sitting here — for tonight, would you be outside. And they move him out under the floor of the hall, and he is spared.

Then the dawn comes, and the temple is not there, and the road is not there, and when he comes to himself he is not in Tsu at all. He is in Hizen, at the other end of the country.

The creatures in the oldest account are not a parade to be watched. They are householders finding a stranger in their hall and putting him somewhere else with something close to courtesy — after which the building he was in turns out never to have been a building.

What the Phrase Was

Put the three together and the shape of the thing before it was painted is fairly clear.

It was a name for a class of night, not a cast of characters. It had dates. It had at least one address. It was invoked by frightened witnesses to explain a single figure in the rain. And in the fullest account of an encounter, the hundred of them behave like residents.

None of that is incompatible with the scrolls, and this note makes no claim about how one became the other. But the popular sentence — that the hyakki yagyō is a procession of yōkai that parades through the streets of the capital on summer nights — is a description of a painting, and the writing that precedes the painting is describing something else: a prohibition, with a horse-headed exception walking down the middle of it reciting a sutra about impermanence.

Sources

1. Uji shūi monogatari 宇治拾遺物語, early 13th century; the tale of the demon at the Ichijō sajiki, book twelve — the figure as tall as the eaves with a horse’s head, chanting shogyō mujō in wind and rain, and the witness’s thought that this might be the hyakki yagyō; and the tale of the practitioner at Ryūsenji in Tsu, book one.
2. Konjaku monogatarishū 今昔物語集, 12th century; the tale concerning the Onidono at Sanjō Higashi-no-Tōin, book twenty-seven.
3. Sakeiki 左経記, the diary of a Heian court official; a dated entry of 1035 using the term kishō.
4. The above passages, the observation that the night parade appears limited to particular days, the reference to the yakō-imi prohibition and to a Heian handbook of court miscellany that describes the danger of violating it, and the counter-case that follows, are read here in a modern multi-volume synthesis of Japanese history, in its section on the period. The quoted passages were not independently collated against editions of the original works for this note.

The readings in “The Man Under the Floor” and “What the Phrase Was” are KWAIDANOTE’s own.