In the past we called Loi krathong as Chong Pa Rieng-floating lantern of royal ceremony. It is a brahman festival to worship Gods-Siva Vishnu and Brahma. When Thai people Buddhism they adapted this ceremony to honor the buddhas cremated bone-the Orignal Buddha at the second heaven ruler.They floated lantern to worship the foot-print of the Buddha on Nammathanati River beach in India.