The Mound of Prince Abo: A Kofun Burial Mound in Ashiya, Japan
Site at a Glance
- Rating
- 3.6
- Popularity
- Very Low
- Country
- Japan
- Primary era
- Classical
- External website
- Open
- Eras represented
- Classical, Early Modern
- Civilizations
- Yamato
- Site type
- Burial
- Remains
- Burial Mound
On this page8 sections
History
The Mound of Prince Abo is a Japanese kofun, or monumental burial mound, in Ashiya, Japan, probably built in the fourth century during the early Kofun period. The individual buried there is unknown. The Imperial Household Agency identifies it as the tomb of Prince Abo, a son of Emperor Heizei, but surviving historical records do not establish that connection.
Prince Abo and the Tomb Tradition
Prince Abo was a member of the imperial family who was sent to serve as Deputy Governor of Dazaifu after becoming involved in the Kusuko Incident of 810, a political conflict at the imperial court. After returning to the capital, he held the offices of Minister of Ceremonial Affairs, Minister of the Imperial Household, Minister of War, and Palace Police Commissioner. During the Jowa Incident of 842, a court conspiracy, he informed the court of the plot. He died on December 1, 842, and was the father of the ninth-century poet Ariwara no Narihira.
The Shoku Nihon Koki records Prince Abo’s death but does not identify his burial place. The Engishiki, a compilation of court regulations and precedents, also gives no location for his tomb. As a result, the site of his burial remained uncertain in antiquity and the medieval period. By the early modern period, several locations were considered possible, including this mound at Uchiide in Settsu Province and the Ozukayama Mound in Kawachi Province.
Edo-Period Alteration and Imperial Designation
The Mori clan, rulers of the Choshu Domain and claimants of descent from Prince Abo, identified the mound as his tomb and undertook substantial repairs during the Edo period. A tradition preserved by Shinnoji Temple states that Mori Tsunamoto renovated the tomb precinct in 1691, during commemorations of the 850th anniversary of Prince Abo’s death. Four bronze mirrors were reportedly discovered during those works.
After the Meiji Restoration, the mound was designated as Prince Abo’s tomb in 1875. It remains under the management of the Imperial Household Agency, the Japanese government institution responsible for imperial mausoleums and related tomb sites. The original designation documents were lost in the Great Kanto Earthquake. The stated basis for the designation included the history of Shinnoji Temple and early modern geographical works.
The mound belongs to the Suigaoka Kofun Group. Komazuka lies to its north, while four burial mounds traditionally known as the Four Mounds formerly stood to the east. Another tradition counted six mounds in the group. Archaeological and conservation-related investigations have continued in modern times, including work in the adjoining eastern area in fiscal year 2004, monitoring during outer-fence repairs in fiscal year 2007, and an Imperial Household Agency investigation of the mound’s external form in fiscal year 2017.
Remains
Mound and Burial Setting
The mound occupies the highest point of the Suigaoka plateau, on the eastern bank of the Miyagawa River along the gradual slope running from the Rokko Mountains toward Ashiya Beach. Its summit reaches 29.854 meters in elevation. The original plan is uncertain, but the surviving mound is about 36 meters in diameter and 3 meters high. A square moat surrounds it, giving the present monument a rounded upper part and square lower outline.
This form is thought to result largely from the Edo-period alterations connected with the tomb repairs. The burial facility itself has not been investigated, so its structure remains unknown. Evidence from the outside of the mound includes stone facing, known as fukiishi, and rows of cylindrical haniwa. These clay funerary objects were commonly placed on or around Kofun-period burial mounds. A straight row of cylindrical haniwa suggests that the original mound may have been either keyhole-shaped or square.
Archaeological Materials
Bronze Mirrors
Shinnoji Temple preserves four bronze mirrors attributed to the mound and traditionally said to have been found during the Edo-period repairs. One is a Lianhu-pattern mirror from the Later Han period. It measures 16.3 centimeters across and weighs 533 grams; its features include a hemispherical central knob, a four-lobed knob seat, and a semicircular opening in the knob.
A second mirror has a triangular rim and a band decorated with waves, three deities, two animals, and a Boshan incense-burner motif, a mountain-shaped image associated with East Asian religious and cosmological ideas. It measures 21.5 centimeters in diameter and weighs 782 grams. Mirrors made from the same mold are known from burial mounds and sites in Hiroshima, Okayama, Nara, and Gifu. Two further mirrors are fragmentary. One, with a triangular rim and a deity-and-animal design, has been reconstructed to about 22 centimeters in diameter and weighs 309 grams. The other is a fragmentary triangular-rimmed deity-and-animal mirror weighing 46 grams.
Stone Belt Fittings
Five stone belt fittings from the Heian period were found among the eastern Four Mounds and are also held by Shinnoji Temple. The group consists of one snake-tail fitting, two round fittings, and two square fittings. Shinnoji Temple’s archaeological materials received designation as Ashiya’s municipal tangible cultural property on March 22, 1990, and some of those materials are regarded as finds from the Mound of Prince Abo.
