The study of ancient India in the context of European colonialism represented an essential intellectual space for the construction of modern concepts of religion, which was not an exclusive domain of Euro-American scholars, but also involved Asian intellectuals. This dissertation explores the role of Indology in the construction of modern Japanese Buddhism within the idea of “world religion” in the period from Meiji to early Shōwa (1868‒1930s). Through the analysis of scholarship on early Buddhism and ancient India, travel accounts, poetry, fiction, visual culture, and periodical publications, this dissertation demonstrates how the study of India provided Japanese Buddhists with cultural tools to redefine the role of religion in modern Japan and the place of Japan in the world. I argue that Japanese Buddhists actively appropriated European Indology and the science of religion, combining them with travel to South Asia and networks with Asian religious reformers and intellectuals, but also reconceiving these ideas within East Asian Buddhist traditions of knowledge. Building on this reimagination of ancient India, Japanese Buddhists strategically deployed scientific, religious, and moral discourse to carve a space for Buddhism in the public sphere of modern Japan through education and periodical publications. Using postcolonial theory, I restore agency to Asian intellectuals in the construction of the concept of religion, but I also reveal the competing nature of the cultural space provided by modern Indology. Japanese Buddhists interpreted ancient Indian civilization and early Buddhism in different ways, using them to propose contrasting views of modern Japan, for example criticizing class discrimination or European imperialism, but also supporting pan-Asian ideas which strengthened Japan’s own imperialist projects in Asia. These observations reveal the ideological and political impact of modern conceptualizations of religion.Chapter 1 analyzes the work of one of the pioneers of modern Indology in Japan, the Buddhist priest-scholar Nanjō Bun’yū, revealing his agency and contribution to the construction of Buddhism as a world religion. Chapter 2 analyzes the Nanjō’s accounts of his travel to India, showing the role that a direct experience of the birthplace of Buddhism had in the construction of his persona as both a scholar and a pilgrim. I use the concept of the imaginaire to analyze the Japanese recontextualization of modern Indology in the intellectual and literary traditions of East Asian Buddhist pilgrimages to India, also revealing the moral interpretation of this travel. Chapter 3 clarifies the meaning of the imaginaire by building on recent theories on religion and visual culture. Through the analysis of artistic and literary sources, I show the impact of the Ajanta murals on Japanese Buddhist priests, artists, and novelists, who framed their approach in both scientific and religious terms, using Ajanta as an inspiration for the production of new aesthetics. Chapter 4 shows how Japanese Buddhists used periodical publications to spread their knowledge of ancient India, using the scientific value of its vast literature to intervene in public debates on a variety of issues. I analyze the reception of Sanskrit literature on love to demonstrate how the use of media to reach a broader public also facilitated the appropriation of Indology for purposes far beyond the aim of Buddhist priests, such as in the erotic grotesque movement’s criticism of sexual repression. In the conclusion, I analyze two further cases of Japanese reimagination of India—the advertisement of a soft drink invented by a Buddhist priest and allegedly inspired by ancient India, and a transnational celebration of the birthday of the Buddha—to summarize my argument about the Japanese strategic deployment of religious and scientific discourse through Indology, to present potential venues for future research, and to conclude with a critical reflection on the ideological use of scholarship on religion.