Adachi Mineichiro was the first non-European and the first Asian President of the Permanent Court of International Justice (1931-1934). This review article introduces the first substantial study of Adachi, focusing on his path of 'becoming' one of a few leading international jurists with non-Euro-American backgrounds in his period. This review essay demonstrates that by examining this Japanese diplomat and jurist, the book, written in Japanese, contributes to the debates on the history of international law in two significant ways. First, it reveals the fundamental issues in the development of the international judicial system, namely the nature of international jurists, empires and the principle of the equality of national sovereignty, and the significance of the roles of non-Euro-American actors in shaping the system. Secondly, it demonstrates the necessity of the inter-disciplinary collaboration between international law, international history and specific regional and national history, as well as methodological challenges in evaluating the historical development of the system.