Development of celestial mechanics in Japan

In this article, a brief history of Japanese astronomy before the Meiji restoration is described at the beginning. Then the development of celestial mechanics research in Japan after the Meiji is traced until the 1950s by describing, particularly, the careers and works of H. Terao, K. Hirayama and Y. Hagihara, the three consecutive professors of celestial mechanics at Tokyo University, as well as those by their students.