'Amalgamation of Buddhas and kami'. A rather vague term applied to the syncretism or synthesis of Buddhism with local religious practices from the Nara period onwards. In line with its assimilative philosophy Buddhism adopted local spirits as 'protectors' of Buddhism, including them in Buddhist rites and soon identifying them as devas or 'trace manifestations'; avatars or local incarnations of Buddhas and bodhisattvas (see e.g. Hachiman, Tenno). Shinbutsu shugo suggests a rather unconscious syncretism between two pre-existing traditions and is often contrasted with specific schools of combinatory thought such as ryobu shinto and sanno-ichijitsu-shinto and the theory of honji-suijaku from which, some Shintoists believe, an ancient and indigenous Shinto later freed itself. However the amalgamation or assimilation of local or imported kami with Buddhist divinities was often deliberate and detailed, and is consistent with the pattern of religious syncretism characteristic of the Buddhist tradition throughout South and East Asia. Adoption as Buddhist objects of worship and identification with eminent Buddhist divinities was the means by which local kami eventually achieved a relatively high spiritual status within the Japanese world-view.
See Shinbutsu bunri.
A Popular Dictionary of Shinto. Brian Bocking.