After years of intrigue, secrecy and much heated debate, some of Japan’s most mysterious monuments will be opened up for public inspection for the first time.

The imposing burial mounds of Japan’s ancient emperors have lain almost untouched for as many as 17 centuries, but after pressure from historians the Imperial Household Agency agreed to let archaeologists get their hands dirty.

As piles of earth and stone dotted around the Japanese countryside go, the mounds may appear unimpressive, but what they conceal could hold the key to unlocking Japan’s imperial past.

There were more than 200,000 ancient burial mounds, or kofun, in Japan, dating back to the 4th century. They come in all shapes and sizes and, though most contain only the remains of local dignitaries, some of the biggest, and the most controversial, are revered as the tombs of Japan’s most famous emperors.

The Imperial Household Agency has faced a problem in recent years: not everyone believes that the mounds contain the remains of emperors. Some archaeologists claim that many of the kofun have been wrongly designated as imperial tombs. They allege that the agency has known for many years that some imperial tombs were wrongly identified, and that those inside may not be as regal as believed.

There are also suspicions that the tombs could reveal that Japan’s emperors were not as Japanese as has been claimed.

Textbook history states that Japan’s emperors have existed in an unbroken line since Jimmu, the great-great-grandson of the Sun Goddess, Amaterasu Omikami. Many historians suspect that, because of repeated intermarriage between Japan and present-day Korea and China, the imperial bloodline could be somewhat more continental.

Although many of the lesser tombs have been freely excavated and explored by historians eager to find out more about daily life in medieval Japan, the imperial mounds have remained off limits.

Historians have long sought permission to study the imperial tombs, to confirm — or rebut — the conspiracy theories but challenging the system has not been straightforward.

Until now, the Imperial Household Agency has refused all requests for inspections, maintaining that the tranquillity of the imperial souls should not be disturbed. Some academics who have campaigned for access have complained of having received death threats from ultra-nationalists.

After all the rejections, the waiting game is finally over. Although a number of restrictions remain, several academic organisations finally have been granted royal permission to visit the Imperial tombs.

On Monday, historians, archaeologists, zoologists and botanists will all be on the guest list, and it promises to be quite a celebration.

The Imperial Household Agency said that the lifting of its restrictions, the day after Emperor Akihito offered his annual New Year’s greetings to nearly 70,000 people at the Imperial Place in Tokyo, represented an effort to aid research into Japan’s ancient history.

The gesture may be merely the cheer of a Japanese New Year, but the mystery of the monarchic mounds could be revealed at last.

Family's sacred treasures

Source: Britannica, Times archive, Japanzone.com, SOAS

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