Abstract

SummaryIn 1684, during the Edo period (1603–1868), the imperial court of Japan passed a reform act that resulted in a new almanac called the Jôkyô almanac. This was the first reform in more than eight hundred years, and marked a departure from the past practice of adopting almanacs from China. Yet, the reform was complicated, and it was achieved after decades through the efforts of Shibukawa Harumi (1639–1715). How was the reform accomplished, and why was it significant? In this study, I will focus on Harumi's role in the reform. I propose to examine the reform as the culmination of a process deeply linked to Harumi's political connections and his intellectual growth especially in the field of calendrical sciences. I will show that this approach of looking at the reform by analyzing different aspects of Harumi's life has implications for understanding trends in society in seventeenth-century Japan. First, despite the ban on Christianity, intellectuals like Harumi assimilated European sciences in unique ways. Second, Harumi's activities exemplified how intellectual ties were increasingly embedded within political networks. Overall, I will argue that the reform of the almanac, viewed as a process surrounding the core figure of Harumi, was driven by scientific goals and personal ambitions.