<論説>イサキオス一世とコンスタンティノス十世の治世をめぐって : 過渡期のビザンツ皇帝政権

Abstract

十一世紀の後半に相次いでビザンツ皇帝となったイサキオス一世とコンスタンティノス十世の治世は、対照的な外見を呈している。前者は典型的な軍人皇帝として軍備強化と厳しい緊縮財政を推進したのに対し、後者は民政を重視し、支持者に気前よく財貨を分配した。本稿の課題は、こうした両者の統治スタイルの違いが、彼らの追求した政治的課題の内容に起因していたことを立証することにある。考察の結果、小アジアの有力貴族出身のイサキオス一世が、自らの社会的背景を無視し、国家公権の強化、皇帝独裁権の確立を図ったことが彼の孤立と最終的な退陣を招いたこと、逆に貴族層の利害を尊重し、王朝樹立に精力を集中したコンスタンティノス十世は、貴族たちへの統制力を低下させ、軍事的危機が深刻化するなかで、充分な支配権を行使できなくなり、それが息子への権力継承の阻害要因になったこと、が明らかになった。

The reigns of lsaakios I Komnenos (1057-1059) and Konstantinos X Doukas (1059-1067) who occupied the Byzantine throne consecutively in the 11th century contrast each other strongly. The former was a typical soldier-emperor who strengthened the military and carried out a policy of retrenchment, while the latter devoted himself to civil affairs and generously distributed public wealth among his supporters. The aim of this paper is to demonstrate that the difference between their styles of government were a result of the character of the political matters on which they concentrated and to seek out the cause of their failure. As a result of our examination, we reached to following conclusions. Isaakios I Komnenos, who came from a powerful Anatolian aristocratic family, failed to take the interests of his fellow aristocrats into consideration. And his effort to create a strong Byzantine state and to establish absolute imperial power resulted in his general isolation and finally compelled him to abdicate. Konstantinos X Doukas, on the other hand, respected the aristocrats' interests and tried hard to establish his dynasty. The adoption of this policy, however, caused him to lose control over powerful aristocrats, making it more difficult than ever to govern the empire. Thus, amidst growing military crisis, his plans to yield the throne to his son and to establish the Doukas dynasty came to end in failure.