A law enacted six years ago has given historians a new powerful weapon to challenge a long-held taboo preserved by the Imperial Household Agency: investigating the secrets of ancient emperors’ tombs.
The weapon is the public information disclosure law, which has allowed Noboru Toike, assistant professor at Den-en Chofu University and an expert on Imperial tombs, to access and obtain copies of internal agency documents.
The documents suggest that the agency, despite official denials, once conducted academic studies to review the attributions for at least 10 ancient tombs that it claims belong to emperors from the early fifth century to the early 13th century.
Toike’s discovery made headlines because it supported a widespread belief by historians and archaeologists that the government’s designations of ancient burial mounds as the tombs of emperors were made on shaky grounds.
“These (documents) show the agency itself had questioned its own attributions of the tombs, and conducted academic research on them at least until around 1958,” Toike told The Japan Times.
“But today, the agency does not allow (scholars) to enter or excavate (emperors’) tombs for academic research. Their position has receded” from decades past, when the documents were compiled, Toike said.
According to the Imperial Household Agency, there are 112 burial mounds nationwide for all 124 past emperors, including Jinmu, the mythical first emperor, and Hirohito, the 124th, who fathered today’s Emperor Akihito.
Some of the tombs contain the remains of more than one emperor.
But the consensus of Japanese archaeologists and historians is that the government’s claims on most of the ancient “Imperial” tombs are academically unacceptable because they lack scientific grounds.
Most of the tombs were designated as emperors’ tombs in the late 19th century, just as Japan was trying to establish a modern state centered on the emperor to compete with the Western powers. The designations on many of the tombs relied on references found in ancient documents and folk legends.
According to Koichi Mori, a tomb expert and professor at Doshisha University, archaeologists have found that only two of the government’s designations for the 42 tombs said to contain emperors who reigned before and during the Kofun (burial mound) Period from the third to seventh centuries are acceptable.
The two are the tomb of Tenji, the 38th emperor, in Kyoto, and a tomb in Nara where the 40th emperor, Tenmu, and the 41st emperor, Jito, are buried together.
“Usually in Japan, no epitaphs were placed in ancient tombs to identify their occupants,” Toike said.
“So you can’t determine the occupant of an ancient tomb with hard evidence. All you can do is to establish a hypothesis by examining the form of the tombs, unearthed articles, historical documents and related geographical names,” he said.
The route to Toike’s discovery started two years ago, when he bought an old mimeographed booklet at a secondhand bookstore in Tokyo.
Toike, taking advantage of the information disclosure law, obtained a copy of the same booklet from the Imperial Household Agency but found it had additional pages and handwritten memos.
Some of the pages in the agency’s copy were dated 1958 — an indication the relevant studies were conducted at least until that year, according to the scholar.
The copy included a list of “reference places” managed by the Imperial Household Agency. In the terminology of the agency, reference places refer to ancient tombs whose occupants have not been identified but could possibly contain a member of the Imperial family.
The list divided the reference places into four categories, depending on the degree of likelihood that the occupant is from the Imperial family.
The list included nine sites designated as possible emperor mounds that were ranked “2-A” or “2,” meaning their chances of authenticity were one below the top category.
“I was surprised because the agency has consistently explained that ‘reference places’ are described as such because they have no idea who their occupants are,” Toike said.
As he examined the booklet, Toike also learned about a special expert committee established in 1935 by the predecessor to the Imperial Household Agency to examine the ancient tombs.
After obtaining more copies of agency documents concerning the committee, Toike found that it concluded that an ancient tomb in Takatsuki, Osaka Prefecture, should be designated as a reference place because it could be the tomb of Emperor Keitai, who reigned during the sixth century. The agency officially said Keitai is buried in the city of Ibaraki in the same prefecture.
Toike stressed the importance of conducting scientific probes on ancient tombs, noting they could unlock a number of historical mysteries related to ancient Japan.
Most large tombs were built during the Kofun Period, when the Imperial regime was in the process of creating the first unified state that would control much of Japan for the first time, he said.
Japanese historians have long and repeatedly demanded that the government allow them to conduct excavations of the “emperor” tombs.
Claiming that the “peace and calm” of the late emperors must be maintained, however, the Imperial Household Agency has refused to allow any excavation or scientific review of any of the tombs designated as being those of past emperors.
The agency argues that excavations of the burial sites are “tantamount to destruction” of the tombs, where the Imperial family has performed traditional religious rites in honor of their ancestors.
But Toike said: “The tombs should be first treated as historical sites to be studied and preserved under the Cultural Properties Protection Law.”