Japanese Emperor Naruhito has performed an elaborate and secretive ritual dating back 1,300 years, giving thanks to the sun goddess Amaterasu as part of his enthronement rites.

Key words: The last major rite of his accession has cost $36.6 million

The last major rite of his accession has cost $36.6 million The secretive and ancient ritual involves symbolically sharing meal with the sun goddess

The secretive and ancient ritual involves symbolically sharing meal with the sun goddess Critics say the practice recalls a militaristic past and is too expensive

He acceded to the throne when his father, Akihito, became the first Japanese monarch to abdicate in two centuries after worrying that advancing age might make it hard to perform official duties.

The Daijosai, considered the most important ritual for Japan's imperial household, came three weeks after Naruhito proclaimed his ascension to the Chrysanthemum Throne and is performed only once in an emperor's reign.

Television footage showed the Emperor in white silk vestments walking slowly through a specially constructed complex of wooden buildings in the imperial palace known as the Daijokyu on Thursday.

Escorted part of the way by servants, Naruhito entered one of two halls where the main ritual would take place overnight.

Sharing a feast with the goddess

As an unseasonably warm night fell over Tokyo, courtiers in traditional robes began to gather and dignitaries, including Prime Minister Shinzo Abe, gathered at an outdoor pavilion.

Soon after, in scenes broadcast live by most television stations, the Emperor, shielded by a ceremonial umbrella and preceded by courtiers holding torches, was ushered through dark wooden corridors. He was followed by Empress Masako, in 12 layered white robes.

The Japanese imperial line is considered to have descended from the sun goddess Amaterasu ( Wikimedia Commons )

The Emperor was to offer newly harvested rice to Amaterasu, from whom the Japanese imperial line is considered to have descended, and other deities of heaven and earth.

In a ritual that was to last two-and-a-half hours, Naruhito was to recite prayers for peace and "share" a feast with the goddess including salmon, abalone, jujube fruit, and millet, washed down with sake.

Empress Masako, wearing a white layered kimono, was to offer her own prayers in separate halls within the Daijokyu.

Other royals and several hundred attendants, including Mr Abe, took part in separate pavilions. No foreigners attend the sacred rite.

The Emperor disappeared from sight after he entered the main hall by torchlight. Throughout the rituals that ended just before dawn on Friday Japanese time, he was to be accompanied only by a lady-in-waiting.

Daijosai ceremony costs $36.6m due to major construction

The rite was mentioned in historical documents dating back as far as the seventh century but was discontinued for more than 200 years because of civil war and financial constraints, starting up again in the late 17th century.

The Daijosai, which is carried out whenever a new emperor ascends the throne, is estimated to cost 2.7 billion yen ($36.6 million), including building and dismantling the Daijokyu and later banquets at the palace.

The Daijokyu complex is built on an area of about 2,700 square metres and consists of around 30 pavilions of different sizes for those performing and observing the rituals.

"It was originally a simple ceremony using natural materials, but it is expensive to replicate it in the modern age," Keiko Hongo, professor at the Historiographical Institute of the University of Tokyo, said.

The buildings are of a traditional, simple construction. The floors are laid with straw mats and the pillars made from logs with unstripped bark.

Kyoto professor John Breen, from the International Research Center for Japanese Studies, said that most coronations had mystical elements.

"This ritual is basically a feast involving the sun goddess and the Emperor," Mr Breen said.

"The Emperor is transformed by partaking of this feast."

The secretive and sacred Daijosai rite was mentioned in historical documents dating back as far as the seventh century. ( AFP )

The rice used in the Daijosai was planted earlier in the year after palace courtiers selected sites using an ancient ritual involving the shells of rare green sea turtles.

Two thin plates made from turtle shells were heated over a flame to produce cracks, which "told" officials to grow the rice in two locations — the ancient capital of Kyoto and the Tochigi region north of Tokyo.

The harvesting in September was also bound in ritual. The day before, rituals were performed to "purify" everyone involved.

On the day, the Emperor's envoys offered prayers and the rice was harvested by farmers in traditional clothes and black hats at the two locations selected.

Only the most carefully selected heads are threshed to make the offerings for the Daijosai.

Critics slam ceremony as too costly

The Daijosai, though not officially a state occasion, has drawn criticism given its highly religious nature and cost.

Critics note that while a Daijosai existed more than 1,000 years ago, the current ritual largely took its form in the late 1800s, as Japan sought to unite the nation around the Emperor.

The head of a group suing to ban the ritual, Koichi Shin, said the rite's nationalistic underpinnings were one reason for their opposition. Another was using public funds to stage it — a complaint echoed by the Emperor's younger brother, Crown Prince Akishino, who said the imperial family's private funds should be used, mandating a smaller rite.

Mr Shin said objections to the Daijosai and other imperial rites were fewer than in 1990, when Akihito ascended the throne, with press coverage less critical and fewer protests. In 1990, 1,700 people sued the government compared to 318 this time.

"We don't expect good results," Mr Shin said.

"But we think it's important to use everything we can to get across the idea that merging religion and state isn't good."

AP/AFP/Reuters