Oni

What it is

An oni is a type of yōkai, or supernatural spirit, found in Japanese folklore. These beings are often described as demons, ogres, or trolls. They are typically portrayed as large, muscular figures with one or more horns on their heads. Their skin may be red, blue, black, or yellow. Oni have massive teeth and sometimes a third eye on their forehead. They are known for their superhuman strength and their ability to change their appearance to trick people. While they are generally seen as evil monsters that eat humans, some stories link them to good fortune and wealth.

Where it comes from

The concept of the oni evolved from the Chinese character guǐ, which means ghost or soul of the dead. In Japan, the word became associated with the idea of hiding. Early texts like the Nihon Shoki describe oni as entities rather than just spirits. The legend of Shuten-dōji, a powerful oni defeated by Minamoto no Yorimitsu, helped shape their image in art and literature. Buddhist influences also played a role, linking oni to wrathful deities and wardens of hell who punish sinners.

Tools and materials

Oni are commonly depicted carrying iron clubs called kanabō. They wear loincloths made from tiger pelts. Their hands and feet have three to six digits tipped with sharp claws. Some descriptions mention a third eye on their forehead. In folk practices, roasted soybeans are used to drive oni away during festivals. Holly leaves and dried sardine heads are also used as charms against them in some regions.

What it is for

Oni are primarily feared as agents of harm. They bring calamities such as war, plague, earthquakes, and eclipses. They are said to cause illness and death, often eating people in a single gulp. However, they are also invoked to dispel bad luck. During certain festivals, people perform rituals to send oni away and invite blessings into their homes. Children's stories use oni to teach obedience through fear.

Peoples and places

Oni are central to Japanese folklore and appear in many traditional tales. Stories like Momotarō feature oni as villains living on distant islands. The Ainu people also have connections to these beliefs through historical dictionaries. In modern times, oni have become less frightening and are often used in playful contexts, such as children's games where one player acts as the oni.

What people believe

In Japanese belief, oni reside in mountains, caves, or hell. They are considered evil beings with substance, unlike disembodied ghosts. Buddhist teachings view wicked souls that cannot be rehabilitated as transforming into oni after death. Only the worst people become oni while alive. They are also linked to Hindu-Buddhist creatures like yakshas and rakshasas, serving as wardens of hell under King Yama.

When it is done

The Setsubun festival in February involves throwing roasted soybeans to drive out oni. This custom began with the aristocracy and spread to the general public. People shout phrases to keep oni outside and bring fortune inside. Regional variations include using specific charms during this season. The northeasterly direction, known as the demon gate, is also associated with oni and is avoided or warded off in architecture.

How scholars and sceptics see it

Scholars note the evolution of the oni from a Chinese ghost concept to a distinct Japanese demon. Some argue that the oni is entirely a product of Buddhist mythology. Skeptics question the historical accuracy of temple alignments designed to block oni. Anthropologists study how oni reflect societal fears of disasters and violence. The transformation of oni in modern media shows a shift from terror to entertainment.

Compare and confuse

Oni are similar to Western ogres and trolls due to their physical traits and monstrous nature. They differ from Chinese guǐ, which are usually formless spirits. The term kishin refers to particularly powerful oni, linking them to Buddhist wrathful deities. In children's games, the role of the oni is playful, contrasting with their terrifying reputation in folklore.

Today

In contemporary Japan, oni have lost much of their original wickedness. They appear in parades to dispel bad luck and are featured in modern media. Oni-faced roof tiles are used on buildings to ward off misfortune. Idioms involving oni are common in daily language. The creature has become a symbol of Japanese culture, appearing in various forms of art and entertainment.

Rites that involve Oni

Days linked to Oni

Questions people ask about Oni

Good reading and sources

• Encyclopaedia BritannicaArticle

• Oni on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos and video
• Wikidata recordOpen data