戦間期国際法の法典化と国際法学者マンレー・Ｏ・ハドソン

――国際連盟とアメリカのはざまで――

抄録

This article aims to examine the process by which the project of codifying international law was initiated in the League of Nations in the 1920s, particularly focusing on the contribution made by an American international lawyer, Manley O. Hudson.

The codification efforts for international law under the aegis of the League of Nations, including the Hague Codification Conference in 1930, are considered to be crucial in the history of international law. During this period, not only did the number of multilateral treaties increase dramatically, but also non-Western states began to participate in treaty negotiations through the forum of the League, and the international law-making process, which had previously been dominated by the Western powers, was transformed into a more universal one.

Nevertheless, the development of international law was not necessarily promised by the establishment of the League Covenant. In the first place, the drafters of the Covenant had little interest in the enhancement of international law in general. This is evidenced by the fact that the Covenant contained only one sentence in the preamble that referred to international law. What is more, at the first Assembly of the League in 1920, a resolution proposing to embark on the project of codification was rejected.

How did the League then change its course and decided to undertake the project for assembling the Hague Conference? The League’s efforts for codification were in fact not solely made for the purpose of development of international law. With the United States showing a keen interest in hosting a codification conference at that time, some League officials were concerned that the role as the bearer of the global legal order would shift from Geneva to Washington. Hudson, who was a temporary member of the Secretariat of the League, strongly shared this concern; he submitted a memorandum to the Secretary-General, Sir Eric Drummond, suggesting the League demonstrate its initiative in codification in order to preserve the League’s presence in the making of global law. With the approval of Drummond, Hudson co-drafted a resolution on the project of codification of international law which was adopted at the Fifth Session of the League’s Assembly in 1924.

Hudson’s proposal became the catalyst for the League to quickly take up the initiative on the codification of international law; it paved the way for the holding of the first codification conference in The Hague. For the League, the codification was one of the means for maintaining its leadership of world order building in relation to the United States.