Yōkai

• First century: there is a book from China titled Xúnshǐ zhuàn 循史傳 with the statement "the spectre (yōkai) was in the imperial court for a long time. The king asked Tui for the reason. He answered that there was great anxiety and he gave a recommendation to empty the imperial room" (久之 宮中数有妖恠（妖怪） 王以問遂 遂以為有大憂 宮室将空), thus using "妖恠" to mean "phenomenon that surpasses human knowledge."
• Houki 8 (772): in the Shoku Nihongi, there is the statement "shinto purification is performed because yōkai appear very often in the imperial court, (大祓、宮中にしきりに、妖怪あるためなり)," using the word "yōkai" to mean not anything in particular, but strange phenomena in general.
• Middle of the Heian era (794-1185/1192): In The Pillow Book by Sei Shōnagon, there is the statement "there are tenacious mononoke (いと執念き御もののけに侍るめり)" as well as a statement by Murasaki Shikibu that "the mononoke have become quite dreadful (御もののけのいみじうこはきなりけり)," which are the first appearances of the word "mononoke."
• Koubu 3 (1370): In the Taiheiki, in the fifth volume, there is the statement, "Sagami no Nyudo was not at all frightened by yōkai."

Yamata no Orochi from the Nihon-ryakushi: Susanoo by Tsukioka Yoshitoshi

The ancient times were a period abundant in literature and folktales mentioning and explaining yōkai. Literature such as the Kojiki, the Nihon Shoki, and various Fudoki expositioned on legends from the ancient past, and mentions of oni, orochi, among other kinds of mysterious phenomena can already be seen in them.[12] In the Heian period, collections of stories about yōkai and other supernatural phenomena were published in multiple volumes, starting with publications such as the Nihon Ryōiki and the Konjaku Monogatarishū, and in these publications, mentions of phenomena such as Hyakki Yagyō can be seen.[13] The yōkai that appear in these literature were passed on to later generations.[14] However, despite the literature mentioning and explaining these yōkai, they were never given any visual depictions. In Buddhist paintings such as the Hell Scroll (Nara National Museum), which came from the later Heian period, there are visual expressions of the idea of oni, but actual visual depictions would only come later in the Middle Ages, from the Kamakura period and beyond.[15]

Yamata no Orochi was originally a local god but turned into a yōkai that was slain by Susanoo.[16] Yasaburo was originally a bandit whose vengeful spirit (onryo) turned into a poisonous snake upon death and plagued the water in a paddy, but eventually became deified as the "wisdom god of the well (井の明神)."[17] Kappa and inugami are sometimes treated as gods in one area and yōkai in other areas. From these examples, it can be seen that among Japanese gods, there are some beings that can go from god to yōkai and vice versa.[18]

The Hyakki Yagyo Emaki, author unknown. It comes from the Muromachi period.

Medieval Japan was a time period where publications such as Emakimono, Otogizōshi, and other visual depictions of yōkai started to appear. While there were religious publications such as the Jisha Engi (寺社縁起), others, such as the Otogizōshi, were intended more for entertainment, starting the trend where yōkai became more and more seen as subjects of entertainment. For examples, tales of yōkai extermination could be said to be a result of emphasizing the superior status of human society over yōkai.[9] Publications included:

• The Ooe-yama Shuten-doji Emaki (about an oni), the Zegaibou Emaki (about a tengu), the Tawara no Touta Emaki (俵藤太絵巻) (about a giant snake and a centipede), the Tsuchigumo Zoshi (土蜘蛛草紙) (about tsuchigumo), and the Dojo-ji Engi Emaki (about a giant snake). These emaki were about yōkai that come from even older times.
• The Kitano Tenjin Engi Emaki, in which Sugawara no Michizane was a lightning god who took on the form of an oni, and despite attacking people after doing this, he was still deified as a god in the end.[9]
• The Junirui Emaki, the Tamamono Soshi, (both about Tamamo-no-Mae), and the Fujibukuro Soushi Emaki (about a monkey). These emaki told of yōkai mutations of animals.
• The Tsukumogami Emaki, which told tales of thrown away none-too-precious objects that come to have a spirit residing in them planning evil deeds against humans, and ultimately get exorcised and sent to peace.
• The Hyakki Yagyō Emaki, depicting many different kinds of yōkai all marching together

In this way, yōkai that were mentioned only in writing were given a visual appearance in the Middle Ages. In the Otogizōshi, familiar tales such as Urashima Tarō and Issun-bōshi also appeared.

The next major change in yōkai came after the period of warring states, in the Edo period.

• Enpō 6 (1677): Publication of the Shokoku Hyakumonogatari, a collection of tales of various monsters.
• Hōei 6 (1706): Publication of the Otogi Hyakumonogatari. In volumes such as "Miyazu no Ayakashi" (volume 1) and "Unpin no Yōkai" (volume 4), collections of tales that seem to come from China were adapted into a Japanese setting.[19]
• Shōtoku 2 (1712): Publication of the Wakan Sansai Zue by Terajima Ryōan, a collection of tales based on the Chinese Sancai Tuhui.
• Shōtoku 6 (1716): In the specialized dictionary Sesetsu Kojien (世説故事苑), there is an entry on yōkai, which stated, "among the commoners in my society, there are many kinds of kaiji (mysterious phenomena), often mispronounced by commoners as 'kechi.' Types include the cry of weasels, the howling of foxes, the bustling of mice, the rising of the chicken, the cry of the birds, the pooping of the birds on clothing, and sounds similar to voices that come from cauldrons and bottles. These types of things appear in the Shōseiroku, methods of exorcising them can be seen, so it should serve as a basis."[20]
• Tenmei 8 (1788): Publication of the Bakemono chakutocho by Masayoshi Kitao. This was a kibyoshi diagram book of yōkai, but it was prefaced with the statement "it can be said that the so-called yōkai in our society is a representation of our feelings that arise from fear" (世にいふようくわいはおくびょうよりおこるわが心をむかふへあらわしてみるといえども ... ),[21] and already in this era, while yōkai were being researched, it indicated that there were people who questioned whether yōkai really existed or not.

It was in this era that the technology of the printing press and publication was first started to be widely used, that a publishing culture developed, and was frequently a subject of kibyoshi[22] and other publications.

As a result, kashi-hon shops that handled such books spread and became widely used, making the general public's impression of each yōkai fixed, spreading throughout all of Japan. For example, before the Edo period, there were plenty of interpretations about what the yōkai were that were classified as kappa, but because of books and publishing, the notion of kappa became anchored to what is now the modern notion of kappa. Also, including other kinds of publications, other than yōkai born from folk legend, there were also many invented yōkai that were created through puns or word plays, and the Gazu Hyakki Hagyo by Sekien Toriyama is one example of that. Also, when the Hyakumonogatari Kaidankai became popular in the Edo period, it is thought that one reason for the appearance of new yōkai was a demand for entertaining ghost stories about yōkai no one has ever heard of before, resulting in some ō that were simply made up for the purpose of telling an entertaining story, and the kasa-obake and the tōfu-kozō are known examples of these.[23]

They are also frequently depicted in ukiyo-e, and there are artists that have drawn famous yōkai like Utagawa Kuniyoshi, Yoshitoshi, Kawanabe Kyōsai, and Hokusai, and there are also Hyakki Yagyō books made by artists of the Kanō school.

In this period, toys and games like karuta and sugoroku, frequently used yōkai as characters. Thus, with the development of a publishing culture, yōkai depictions that were treasured in temples and shrines were able to become something more familiar to people, and it is thought that this is the reason that even though yōkai were originally things to be feared, they have then become characters that people feel close to.[24]

"The Heavy Basket" from the Shinkei Sanjurokkei Sen by Tsukioka Yoshitoshi (Meiji 25)

• Meiji 24 (1891): Publication of the Seiyuu Youkai Kidan by Shibue Tamotsu. It introduced folktales from Europe, such as the Grimm Tales.
• Meiji 29 (1896): Publication of the Yōkaigaku Kogi by Inoue Enryō
• Meiji 33 (1900): Performance of the kabuki Yami no Ume Hyakumonogatari at the Kabuki-za in January. It was a performance in which appeared numerous yōkai such as the Kasa ippon ashi, skeletons, yuki-onna, osakabe-hime, among others. Onoe Kikugorō V played the role of many of these, such as the osakabe-hime.
• Taishō 3 (1914): Publication of the Shokubutsu Kaiko by Mitsutaro Shirai. Shirai expositioned on plant yōkai from the point of view of a plant pathologist and herbalist.

With the Meiji Restoration, Western ideas and translated western publications began to make an impact, and western tales were particularly sought after. Things like binbogami, yakubyogami, and shinigami were talked about, and shinigami were even depicted in classical rakugo, and although the shinigami were misunderstood as a kind of Japanese yōkai or kami, they actually became well known among the populace through a rakugo called "Shinigami" in San'yūtei Enchō, which were adoptions of European tales such as the Grimm fairy tale "Godfather Death" and the Italian opera "Crispino" (1850). Also, in Meiji 41 (1908), Kyōka Izumi and Tobari Chikufuu jointedly translated Gerhart Hauptmann's play The Sunken Bell. Later works of Kyōka such as Yasha ga Ike were influenced by The Sunken Bell, and so it can be seen that folktales that come from the West became adapted into Japanese tales of yōkai.

Since yōkai are introduced in various kinds of media, they have become well known among the old, the young, men and women. The kamishibai from before the war, and the manga industry, as well as the kashi-hon shops that continued to exist until around Showa 40 (the 1970s), as well as television contributed to the public knowledge and familiarity with yōkai. Yōkai play a role in attracting tourism revitalizing local regions, like the places depicted in the Tono Monogatari like Tono, Iwate, Iwate Prefecture and the Tottori Prefecture, which is Shigeru Mizuki's place of birth.

In this way, yōkai are spoken about in legends in various forms, but traditional oral storytelling by the elders and the older people is rare, and regionally unique situations and background in oral storytelling are not easily conveyed. For example, the classical yōkai represented by tsukumogami can only be felt as something realistic by living close to nature, such as with tanuki (Japanese raccoon dogs), foxes and weasels. Furthermore, in the suburbs, and other regions, even when living in a primary-sector environment, there are tools that are no longer seen, such as the inkstone, the kama (a large cooking pot), or the tsurube (a bucket used for getting water from a well), and there exist yōkai that are reminiscent of old lifestyles such as the azukiarai and the dorotabo. As a result, even for those born in the first decade of the Showa period (1925–1935), except for some who were evacuated to the countryside, they would feel that those things that become yōkai are "not familiar" are "not very understandable." For example, in classical rakugo, even though people understand the words and what they refer to, they are not able to imagine it as something that could be realistic. Thus, the modernization of society has had a negative effect on the place of yōkai in classical Japanese culture.

On the other hand, the yōkai introduced through mass media are not limited to only those that come from classical sources like folklore, and just as in the Edo period, new fictional yōkai continue to be invented, such as scary school stories and other urban legends like kuchisake-onna and Hanako-san, giving birth to new yōkai. From 1975 onwards, starting with the popularity of kuchisake-onna, these urban legends began to be referred to in mass media as "modern yōkai."[25] This terminology was also used in recent publications dealing with urban legends,[26] and the researcher on yōkai, Bintarō Yamaguchi, used this especially frequently.[25]

During the 1970s, many books were published that introduced yōkai through encyclopaedias, illustrated reference books, and dictionaries as a part of children's horror books, but along with the yōkai that come from classics like folklore, Kaidan, and essays, it has been pointed out by modern research that there are some mixed in that do not come from classics, but were newly created. Some well-known examples of these are the gashadokuro and the jubokko. For example, Arifumi Sato is known to be a creator of modern yōkai, and Shigeru Mizuki, a manga artist for yōkai, in writings concerning research about yōkai, pointed out that newly created yōkai do exist,[27][28] and Mizuki himself, through GeGeGe no Kitaro, created about 30 new yōkai.[29] There has been much criticism that this mixing of classical yōkai with newly created yōkai is making light of tradition and legends.[27][28] However, since there have already been those from the Edo period like Sekien Toriyama who created many new yōkai, there is also the opinion that it is unreasonable to criticize modern creations without doing the same for classical creations too.[27] Furthermore, there is a favorable view that says that introducing various yōkai characters through these books nurtured creativity and emotional development of young readers of the time.[28]