K. Sasaki
The highest rank was symbolized by decorated swords. While keyhole- shaped tumuli comprised
only 1 percent of sixth- century mounded tombs, 25 percent of the tombs (thirty- nine in all) from
which decorated swords have been excavated are keyhole- shaped. The rest are large circular
mounded tombs of more than 30 meters in diameter. Moreover, sarcophagi with gambrel- roof lids
are found in the corridor- style burial chambers of the majority of the tombs in the region of the
central polity from which decorated swords have been excavated. Decorated swords are often
accompanied by iron armor, bronze mirrors, bronze bowls, and sometimes gilt- bronze crowns and
gilt- bronze decorated shoes.^31
While corridor- style horizontal burial chambers dominated until the middle seventh century,
the construction of keyhole- shaped tumuli ended in most of the regions in Japan in the fourth
quarter of the sixth century, and at the beginning of the seventh century in a few regions of the
Kanto. The last (newest) keyhole- shaped tomb in the Nara Basin was the Gojōno-Maruyama (or
Mise- Maruyama) tomb, 310 meters in length. Some scholars believe it to have been Emperor
Kinmei’s mausoleum, although the Imperial Household Agency (Kunaichō) designates another
late sixth- century tumulus as Kinmei’s.
In the third quarter of the sixth century, large circular and square tombs gradually replaced
keyhole- shaped mounds for the burials of very high- ranking nobles in the Nara Basin. One
piece of the background to the decline of keyhole- shaped tumuli may be the introduction of
Buddhism to Japan from Paekche, Korea around this era. In 588, the construction of the first
major Buddhist temple, Asuka- dera, began in the southeastern corner of the Nara Basin, an
area called Asuka, where palaces were constructed in the seventh century. In the seventh
century, erecting Buddhist temples became the premier status symbol, replacing the construc-
tion of mounded tombs. The decline of keyhole- shaped tumuli in the middle sixth century and
after was, in a sense, a prelude to the practice of erecting Buddhist temples in the following
century.
The Nihon shoki mentions several miyake, or royal estate in regions, far away from Nara, such
as in Musashi (in present- day Saitama prefecture) and Tsukushi (in present- day Fukuoka prefec-
ture) during the reign of Emperor Ankan (traditional dates, 534–535). Miyake were complexes of
rice paddies, store houses, and office buildings in which the managers of the rice paddies worked,
and the rice paddies were under the direct control of the newly restyled imperial court. In addi-
tion to the miyake, the central court directly controlled many aspects of production and distribu-
tion, including trade, by the middle sixth century. This is archaeologically evidenced by the
spatial distribution of high- quality gold or gilt- bronze objects far away from Nara.
Even in this period, however, some local polities in eastern Japan remained somewhat auto-
nomous. Especially in a region fifty miles northeast of Tokyo, the old province of Hitachi, or
what is now Ibaraki prefecture, the construction of keyhole- shaped tumuli continued until the
beginning of the seventh century. This region also resisted the adoption of the corridor- style
horizontal burial chambers, and maintained the type of burial chambers typical of the fourth and
fifth centuries, until the third quarter of the sixth century.
In a few areas in eastern Japan, locally paramount chiefs were buried in simple tunnel tombs
dug into cliffs, without any mounds at all. This is evidenced by the deposit of gilt- bronze deco-
rated swords, a symbol of authority since the middle sixth century. In these areas, the second-
ranking chiefs were buried in mounded tombs. It is also the case in these areas that the significance
of keyhole- shaped burial mounds as a status symbol was not adopted.^32
In sum, while the construction of keyhole- shaped tumuli declined in the sixth century, control
by the central polity over local regions became stronger. In this sense, society and polity in the
sixth and seventh century may have crossed the threshold into statehood, although archaeologi-
cal evidence for a standing army is not apparent. Still, some local polities remained somewhat