Millenarism in Thailand has found its expression in the religious movements inspired by "phi bun" or "phu mi bun". In modern times, it developed into peasant revolts in 1902 which were followed, at least, two minor "revolts" in 1924 and 1959. All of these "phi bun" movements occurred in the Northeast. Typologically, "phi bun" shares many common traits with millenarian movements in other part of the world. Its topographical concentration in the Northeast may be explained by the fact that the peasants of this region have been suffering from a perennial poverty caused by low and unstable productivity in rice-cultivation in the region. "Nam mon" or sacred water ritual in popular Buddhism, combined with the belief of "future Buddha" and/or the "ideal king", has provided an ideological framework in which "phi bun" religious movements were formulated. The existence of popular Buddhistic belief in such a form as "phi bun" may be exploited by some political forces which aim to threaten the national integrity of Thailand.