The Japanese realm of the sacred in its historical form has, since the dawn of time, been imbued with animistic, indigenous beliefs in supernatural deities, which subsequently evolved into the constitution of Shintō. With the arrival of Buddhism in the Japanese archipelago in the sixth century, a peculiar amalgam emerged, permanently defining Japanese culture, its syncretism, permeability, and openness to influences, particularly from China. Enriching the religious landscape with Confucianism, Daoist teachings as well as the phenomenon of sects (new religious movements), Japanese religiosity exemplifies an unusual fusion of philosophical and spiritual elements. The aim of this article is to provide an overview of the peculiarities of Japan’s religious mosaic, the dynamics of the intermingling of various philosophical currents and, and to demonstrate the idiographic nature of the religious landscape of contemporary Japan. The latter, as it turns out, is a fractious example of East Asian multiculturalism, open to religious eclecticism, syncretism, and mutual borrowing. A theoretical grasp of the above will be complemented by a presentation of two syncretic strands, namely shinbutsu-shūgo and shugendō.