The Customs of Eyo in Okayama Prefecture

The Eyo Customs of Okayama Prefecture: Sacred Naked Festivals That Welcome Spring

Deep in the heart of Okayama Prefecture, on cold February nights, thousands of men strip down to white loincloths, pour icy water over their bodies, and surge into temple halls to compete for two slender wooden talismans. This is Eyo (会陽) — a centuries-old constellation of sacred festivals that has earned Okayama recognition as one of Japan's most distinctive folk culture regions. Designated by the Agency for Cultural Affairs as an Intangible Folk Cultural Property requiring documentation in 2003, the Eyo customs of Okayama offer visitors a rare window into living Japanese folk Buddhism — raw, prayerful, and unforgettable.

What Is Eyo?

The word "Eyo" (会陽) literally means "to meet the yang" — a poetic way of saying "to greet the returning sun and the coming of spring." It refers to a family of New Year naked festivals (hadaka matsuri) preserved at a number of temples and shrines, primarily in the southern part of Okayama Prefecture.

Each Eyo grew from the same Buddhist root: the Shushōe (修正会), a solemn ritual held in the opening days of the year in which monks chant continuously for national peace, abundant harvests, and the happiness of all people. At the close of these prayers, sacred protective amulets were once distributed to worshippers. Over the centuries, the eager scramble for those blessed amulets transformed into the dramatic naked festival we see today, in which two wooden talismans called shingi (宝木) are thrown into a sea of bare-skinned men who fight to claim them and the year's good fortune.

Although the Saidaiji Eyo in Okayama City is the most internationally famous, Eyo is a regional phenomenon, not a single event. Versions of the festival are still held at temples such as Kinzan-ji, Saidaiji Kannon-in, and Anyo-ji in Mimasaka City. Together they form a layered cultural landscape that the national government has chosen to protect as a complete tradition.

Why It Was Recognized as a Cultural Property

On February 20, 2003, the Agency for Cultural Affairs selected "The Eyo Customs of Okayama Prefecture" as an Intangible Folk Cultural Property for which records and documentation should be created. A comprehensive survey report was published by the Okayama Prefectural Board of Education in 2007, followed by a full video documentation in 2010. In 2016, one element of these customs — the Saidaiji no Eyo — was further elevated to the status of Important Intangible Folk Cultural Property of Japan.

Three qualities earned this recognition. First, the Eyo customs preserve, in extraordinary completeness, the medieval Japanese practice of transforming a Buddhist liturgy (Shushōe) into a community folk ritual. Second, the geographic concentration — multiple temples in Okayama keeping the same essential rite alive across centuries — is unique in the country. Third, the festivals continue to function as living religious practices, not staged reconstructions: the prayers are real, the cold water purification (mizugori) is genuine, and the participants come not merely to perform but to receive blessings.

The Heart of the Ritual

Preparation and Purification

Eyo is not a single night but a long arc of preparation. At Saidaiji, for example, the cycle begins three weeks beforehand with a ceremony to retrieve the wood that will be carved into shingi. The next day, master craftsmen shape the talismans. Fourteen days before the festival, the great Shushōe begins, with priests chanting continuously before the principal image of the thousand-armed Kannon, praying for peace, abundance, and the joy of all people.

The Night of the Festival

As darkness falls on the festival evening, men in white fundoshi loincloths stream into the temple precincts to chants of "Wasshoi! Wasshoi!" They cleanse themselves at the kori-tori-ba — a stone basin where ice-cold water is poured over the body in a rite called mizugori. Then comes ji-oshi, a procession that winds through the grounds, building heat and unity, before participants pack onto the great wooden floor of the main hall for hon-oshi, the deep, surging press of bodies.

The Throwing of the Shingi

At the climax of the night, the lights are extinguished. From a high window in the main hall called the gofukumado, the head priest releases two sacred shingi — short cylinders of fragrant wood, wrapped in paper amulets — into the darkness above the crowd. What follows is a ferocious yet ritualized scramble. The man who finally emerges with a shingi rushes to a designated reception station and plants it upright in a wooden masu measure heaped with white rice. Once the shingi is verified, he is proclaimed fukuotoko — the year's "lucky man" — and the talisman is then received by a sponsor (iwainushi) who carries the blessing into the new year.

The Family of Okayama Eyo Festivals

Saidaiji Eyo (Okayama City)

Held on the third Saturday of February at Saidaiji Kannon-in, this is the most renowned of the Okayama Eyo festivals and one of Japan's three great oddly-named festivals (Nihon Sandai Kisai). Some 10,000 men in loincloths compete for the shingi before tens of thousands of spectators. Tradition traces the throwing of amulets to 1510, when the priest Chū-a is said to have first cast protective papers down upon the hopeful crowd.

Kinzan-ji Eyo (Okayama City)

Held on the first Saturday of February at Kinzan-ji Temple — perched on the slopes of Mount Kinzan and once the head temple of forty-eight Bizen-region temples — this is the season's opening Eyo and is said to span more than six hundred years of unbroken practice. Two shingi, called yin and yang, are thrown to participants after a preliminary contest with five smaller shingi.

Anyo-ji Eyo (Mimasaka City)

Held on the second Saturday of February at Anyo-ji Temple in northern Okayama, this Eyo is said to count nearly eight hundred years of history, making it one of the oldest in the prefecture. Around eight hundred men gather here under brutally cold mountain skies to compete for the shingi, and a special children's Eyo is also held the same day.

Highlights for Visitors

For overseas visitors, Eyo offers something almost no other Japanese festival can: the simultaneous experience of solemn Buddhist liturgy and primal physical drama. Whether you come to participate (men aged thirteen and over may register at most temples, subject to conditions) or to watch from a safe vantage point, the experience is unforgettable.

The senses are overwhelmed in the best way. The hiss of cold water hitting bare skin in the kori-tori-ba; the rolling chant of "Wasshoi!" echoing off temple eaves; the warm steam rising from thousands of bodies into a winter night; the sudden plunge into darkness as the lights are killed for the shingi throw; the roar that follows. Around the festival, supporting events bring a different kind of warmth: the all-female Eyo Taiko drumming, the opening Eyo Jinku folk dance, fireworks lighting up the cold sky, and food stalls lining the approaches.

Even outside the festival nights themselves, the host temples reward a visit. Saidaiji Kannon-in possesses an Important Cultural Property bronze bell from the Goryeo dynasty, a Prefecturally Designated three-storied pagoda, and the dignified atmosphere of a Shingon Buddhist mountain temple.

Surrounding Attractions

Okayama Prefecture is one of Japan's most rewarding regions for travelers seeking a balance of history, art, and natural beauty. After experiencing Eyo, consider extending your trip to take in the wider area.

• Korakuen Garden — One of Japan's three great traditional gardens, famed for its borrowed-scenery views of Okayama Castle.
• Okayama Castle — Known as "Crow Castle" for its black exterior, a striking riverside silhouette in the heart of the city.
• Kurashiki Bikan Historical Quarter — White-walled merchant warehouses along willow-lined canals, just a short train ride from Okayama Station.
• Bizen ware pottery villages — The kilns of Bizen and Imbe produce one of Japan's six oldest pottery traditions.
• Naoshima and the Setouchi art islands — Reachable from Okayama Prefecture, an internationally celebrated cluster of contemporary art destinations.