@article{oai:rekihaku.repo.nii.ac.jp:00000593,
 author = {小沢, 洋 and Ozawa, Hiroshi},
 journal = {国立歴史民俗博物館研究報告, Bulletin of the National Museum of Japanese History},
 month = {Mar},
 note = {application/pdf, 古墳時代の上総南西部には２つの強大な政治領域が存在していた。一つは小櫃川流域の馬来田国であり，もう一つは小糸川流域の須恵国である。この両地域では古墳時代のほとんどの期間を通じて継起的に大形古墳の築造が認められ，房総の諸首長層の中でも，とりわけ安定した勢力を維持していたことが窺われる。
小糸川流域では，前期の段階には中・下流域の丘陵上に前方後方墳が拠点的に存在する状況であるが，中期以降には下流沖積地の内裏塚古墳群を中心に首長墓群が形成される。５世紀中頃に房総最大の前方後円墳・内裏塚古墳が築かれて後，６世紀前半代など一時的に首長墓の存在が不明確な時期もあるが，６世紀後半期には継続的な100m級前方後円墳の築造が見られ，中小規模の前方後円墳・円墳を含めた首長系集団の墓域を形成する。７世紀代に入ると，割見塚古墳を始めとする幾つかの方墳が築造され首長系集団の墓制が一新される。これらの方墳は二重周堀・切石積石室といった強い共通性を有しており，房総諸地域の斉一的な終末期方墳形成の中での階層的な意味付けがあったと考えられる。
小櫃川流域では，前期の段階にすでに中流域の小櫃地区を本拠とする首長勢力があり，飯籠塚古墳・白山神社古墳といった大形前方後円墳が築かれている。しかし中期に入ると高柳銚子塚古墳を初現として下流沖積地の祇園・長須賀地区に一貫して首長墓群が形成されるようになり，以後は小糸川流域と非常によく似た展開をたどる。ただし小櫃川流域の首長墓の多くが今日では消滅しているため，編年的関係が不明な部分も多い。また６世紀末葉の金鈴塚古墳を最後に，小櫃川流域では終末期の首長系古墳（方墳）が確認されておらず，上総最古の寺院・大寺の出現と関連してその動向に大きな疑問が残されている。, There existed two powerful political blocks in south-western Kazusa in the Tumulus Period. One was the Makuta-koku in the basin of the Obitsu River, and the other was the Sue-koku in the basin of the Koito River. In these two areas, the continuous construction of large tumuli can be observed through almost all the stages of the Tumulus Period. This indicates that these areas maintained a particularly stable power among the various chiefs in the Bôsô area.
In the basin of the Koito River, in the early part of the Tumulus Period, small and medium-sized keyhole tombs with quadrangular rear mound existed on the hills of the middle and lower reaches of the river. However, in the middle to later period, groups of chiefs' tombs were formed centering around the Dairizuka Tumuli Group on the alluvial plain of the lower reaches. After the Dairizuka Tumulus, the largest keyhole-shaped tumulus in the Bôsô, was constructed in the middle of the 5th century, there was a period in the first half of the 6th century, when there is uncertainty about the existence of chiefs' tombs. Then, in the latter half of the 6th century, there was continuous construction of 100m-long keyhole-shaped tumuli, and tomb areas for the chief family group were formed, including small and medium-sized keyhole-shaped and circular mounds. In the 7th century, several square tombs, including the Warimizuka Tumulus, were constructed, and the tomb system of the chief's family group went through a complete change. These square tumuli had very strong common features, such as double surrounding ditches, and ashlared stone rooms. It can be assumed that there was a class significance in the uniform formation of square tumuli of the final period in the various areas in the Bôsô District.
In the basin of the Obitsu River, there was already a chief power based in the Obitsu district on the middle reaches of the river, and large keyhole-shaped tumuli, such as the Igozuka and Hakusan-Jinja Tumuli, were constructed. In the middle Tumulus Period, however, chiefs' tomb groups were consistently formed in the Gion and Nagasuka districts on the alluvial plain of the lower reaches, the Takayanagi-Chôshizuka Tumulus being the first example. Thereafter, the development is notably similar to that in the basin of the Koito River. However, many of the chiefs' tombs in the basin of the Obitsu River have disappeared, a large part of the chronological relationship is not clear. Furthermore, with the Kinreizuka Tumulus built at the end of the 6th century is as the last example, after which no chief-type tumuli (square mounds) are to be seen in the basin of the Obitsu River. This leaves a large question concerning trends in their relationship to the appearance of the Odera, the oldest temple in Kazusa.},
 pages = {329--366},
 title = {上総南西部における古墳終末期の様相},
 volume = {44},
 year = {1992},
 yomi = {オザワ, ヒロシ}
}