Kyo Arai President
Welcome to the website of the Japanese Society of International Law.
The Japanese Society of International Law was founded in 1897 and marks its 129th year in 2026. It is Japan’s oldest academic society in the field of law and one of the oldest national societies of international law in the world. Over the course of its history, the Society has been closely engaged with the major developments of the modern era, including the revision of the unequal treaties, two world wars, Japan’s withdrawal from the League of Nations, and the reconstruction of the international order following the Second World War.
Professor Shigeru Oda, a devoted supporter of the Society throughout much of its history, passed away last year at the age of 100. He served as a Judge of the International Court of Justice for three consecutive terms totalling twenty-seven years, a record unmatched in the Court’s history, and spent his career advocating that international lawyers should be of practical use in the real world. The Shigeru Oda Prize, established through his generosity, provides a means by which his legacy and the Society’s traditions are passed on to the next generation. The effort and seriousness that students bring to their submissions for this prize are a source of genuine encouragement, and a sign that Professor Oda’s conviction lives on. In the Avant-propos to the inaugural issue of the Journal, the Society described Japan’s entry into the international community and its attainment of “civilized nation” status in terms of both the obligations that membership entailed and the rights it conferred. After 129 years, we are not in a position to accept those words at face value or to endorse the assumptions behind them. The concept of “civilized nations” reflected an international legal order that designated certain states as agents of civilization while placing others under governance or tutelage. This dimension of the Society’s history calls for honest and critical reflection. Although decolonization was formally declared decades ago, unequal relationships between former colonial powers and formerly colonized or occupied peoples persist, and issues relating to self-determination and the disposition of territory remain unresolved. Engaging seriously with international law requires that we examine this history critically rather than take it as given. The Japanese Society of International Law is committed to approaching its work in that spirit.
The Society also faces a significant structural challenge. Demographic trends and changes in the university sector in Japan are expected to accelerate a decline in membership and a contraction of the Society’s financial base over the next fifteen years. In response, the Board of Directors established a committee to carry out a data-driven assessment of the Society’s outlook and identify measures to secure its long-term sustainability. The committee’s report, submitted to the Board in March 2026, argues against accepting decline as inevitable. Instead, it recommends that the Society strengthen its scholarly contribution by focusing resources on its core activities, making greater use of external support, and raising its international profile. Specific recommendations include improving the international visibility of the Society’s activities, making fuller use of the Society’s cross-disciplinary coverage of public international law, private international law, and international politics and diplomatic history, and revising membership and participation arrangements to make the Society more accessible and inclusive. The report also emphasizes the importance of enabling members with caregiving responsibilities or in precarious employment to participate more fully, and of ensuring that early-career scholars have a meaningful role in governance and strategic planning, not just in carrying out unilaterally assigned tasks.
How the Society responds to this report and translates its recommendations into practice is a matter for ongoing discussion among its members. We welcome the views and comments of both members and non-members alike as we consider the way forward.
July 2026
President of the Japanese Society of International Law
Kyo Arai