- 著者
-
吉水 眞彦
- 出版者
- 国立歴史民俗博物館
- 雑誌
- 国立歴史民俗博物館研究報告 = Bulletin of the National Museum of Japanese History (ISSN:02867400)
- 巻号頁・発行日
- vol.179, pp.199-228, 2013-11
天智天皇の近江大津宮は667年,後飛鳥岡本宮から遷都され,5年数ヶ月を経た672年の壬申の乱によって廃都と化した短命の宮都である。7世紀代の宮都で大和以外の地へ宮都が移されたのは前期難波宮と大津宮だけである。その一つである大津宮跡は,現在,琵琶湖南湖南西岸の滋賀県大津市錦織に所在することが判明している。大津宮の実像を知るために宮の構造や白鳳寺院の実態,周辺の空間構造を発掘調査で確認された遺構や出土遺物である第一次資料を再評価することと新たな発掘資料も加えて検討した。その結果,大津宮の特殊性が見えてきた。すなわち,対高句麗外交や軍事上の拠点整備を推進するために陸上・湖上交通の整備に重心が置かれ,大津宮の形が短期間のうちに推進されていた点である。大津宮遷都前夜までの比叡山東麓地域は,渡来系氏族の大壁建物や掘立柱建物の集落が営まれ,また各氏族による穴太廃寺や南滋賀廃寺などの仏教寺院も建立されており,周辺には萌芽的な港湾施設も存在していたものと推定される。このように遷都を受け入れる環境が一定程度整備されていた地域に大津宮は移されたのである。そして遷都の翌年,錦織の内裏地区の北西方の滋賀里に周辺寺院の中では眺望の利く最も高所に崇福寺を新たに造営し,対照的に宮の東南方向の寺院の最低地にあたる現在の大津市中央三丁目付近の琵琶湖岸にほぼ同時期に大津廃寺を建立した。つまり崇福寺跡と大津廃寺は川原寺同笵軒丸瓦を共通して使用していることから,大津宮と密接な関係がみられ,前者には城郭的要素があり,後者には木津川沿いの高麗寺と「相楽館」のような関係を有する港湾施設を近隣に配置し,人と物の移動ための機動力を重視して造営された。これらに触発されたかのように周辺氏族は穴太廃寺の再建例にみられるように再整備を行なっている。このように大津宮の内裏地区や,大津廃寺を除いた仏教寺院は高燥の地に立地し,かつ正南北方位を意識した配置がみられるのに対して,木簡などを出土した南滋賀遺跡の集落跡などは低地に営まれ,かつ正南北方位を意識しない建物を構築している。おそらく内裏地区や白鳳寺院,諸機能を分担した各施設は整斉に計画され,その周辺には地形に左右された集落などが混在した空間を呈していたものと思われる。近江朝廷の内裏や寺院・関係施設などを短期間に新設し,ハード面を充実させていくにつれて渡来系集落的景観から大津宮の交通整備重視の未集住な空間へと変遷していったものと考えた。Omi Otsu no Miya of the Emperor Tenchi was a short-lived imperial capital, which was relocated from Nochi no Asuka no Okamoto no Miya in 667, and a little over 5 years later, abandoned due to the Jinshin War in 672. From among all the imperial capitals of the 7th century, the only capitals relocated to other locations than the Yamato Province were the Early Naniwa no Miya and Otsu no Miya. Archaeological research has placed Otsu no Miya on the southwestern shore of Lake Biwa, in the current district of Nishikori, Otsu City, Shiga Prefecture.To understand the historical character of Otsu no Miya, its location and structure, the actual conditions of Hakuho Temple, and the spatial structure of the surrounding area was studied by reexamining the primary materials, mainly the ancient foundations and artifacts excavated by earlier digs, along with some newer excavated materials. As a result, several special characteristics of Otsu no Miya were found. Namely, to promote the establishment of a base for both diplomatic relations with Koguryo and military purposes, priority was given to the development of land and lake transportation, and the establishment of Otsu no Miya was promoted for only a short period of time.Up to right before the relocation of the capital to Otsu no Miya, in the area at the eastern foot of Mt. Hiei, Chinese and Korean clan settlements consisting of large walled buildings and dug-standing pillar buildings existed along with such Buddhist temples as the Ano Temple (abandoned) and Minami-Shiga Temple (abandoned) built by these clans; it can be inferred that in the surrounding areas the early stages of port facilities existed. Otsu no Miya was relocated to such an area in which to a certain extent an environment suitable for the relocation of the capital was being developed. In the year following the relocation, Sofukuji Temple was newly built at Shigasato, lying northwest of the Imperial Palace in Nishikori; the temple had a fine view and the site was the highest among the surrounding temples; at nearly the same time, in contrast, Otsu Temple (abandoned) was built in the lowest position of all the temples, southeastward from the Miya, on the shores of Lake Biwa in the current Hamaotsu. Since the Sofukuji Temple site and the Otsu Temple (abandoned) both used round-shaped roof tiles produced from the same tile mold as used at Kawara-dera Temple, a close relation with Otsu no Miya can be considered. The Sofukuji Temple was fortified to some extent, and the Otsu Temple (abandoned) was constructed with a focus on mobility for the transport of people and goods, and its nearby port facilities had a relation with Komadera Temple at Kizu River like "Sagaraka no Murotsumi" (guest house). As if inspired by such construction work, the clans in the surrounding areas carried out their own redevelopment as shown by the rebuilding of Ano Temple (abandoned). As mentioned above, the Palace area of Otsu no Miya and Buddhist temples apart from Otsu Temple (abandoned) were located on the higher and dry sites and arranged along a north and south line, whereas the settlement sites of the Minami- Shiga site, from which mokkan (a narrow strip of wood on which an official message is written) were excavated, were laid out on low-lying land and buildings constructed with no attention to a north/south axis. It is probable that the Palace area, Hakuho Temple, and each institution with an allocated function, were arranged in accordance with a deliberate and ordered plan, and the layout of its surrounding settlements was affected by the topography; these two different approaches coexisted in one spatial structure.In the author's view, the Palace of the Omi Imperial Court, temples and related facilities were newly established over a short period of time, and as the physical infrastructure was improving, the landscape of Chinese and Korean clan settlements was changing to a space with no settlements and a focus on developing transportation links for Otsu no Miya.