Shinbutsu-shūgō, also called Shinbutsu shū Shinbutsu-konkō, is the syncretism of Shinto and Buddhism that was Japan's main organized religion up until the Meiji period. Beginning in 1868, the new Meiji government approved a series of laws that separated Japanese native kami worship, on one side, from Buddhism which had assimilated it, on the other.

Syncretism is the practice of combining different beliefs and various schools of thought. Syncretism involves the merging or assimilation of several originally discrete traditions, especially in the theology and mythology of religion, thus asserting an underlying unity and allowing for an inclusive approach to other faiths. While syncretism in art and culture is sometimes likened to eclecticism, in the realm of religion, it specifically denotes a more integrated merging of beliefs into a unified system, distinct from eclecticism, which implies a selective adoption of elements from different traditions without necessarily blending them into a new, cohesive belief system. Syncretism also manifests in politics, known as syncretic politics.