Abstract
Theravada Buddhism is the official religion in Laos and the ethnic Lao have been denying, theologically and historically, spirit cults (phi). However, many researchers have found that the spirit cults remain strong in practice, and are sometimes mingled strongly with Buddhism. Even in Luang Prabang, the royal capital of Laos until 1975, where supremacy of Buddhism, as the official religion of the kingdom, was and still is especially emphasized and where residents express negative attitude toward spirit cults, some aspects of the cults can be noticed in their rituals. Specifically, influence of the spirit cults is observed in the Buddhist rituals related to ceremonial boat races, including the “boat spirit” worship deriving from the sacred tree from which the boats are manufactured, the rite of Phou Ngeu Nya Ngeu deities, and veneration of the Naga (mythological river deity). These are carefully integrated into Buddhism through justifying procedures and are considered to be separated from general spirit cults.