The origins and symbolism of Khmer weddings, according to the Khmer Institute:
Khmer weddings enact Cambodia’s greatest legend. The first Khmer prince, Preah Thong, fell in love with the Naga Princess, Neang Neak, while exiled from his homeland. As a marriage gift to the couple, the father of the Naga Princess swallowed part of the ocean, and out of this was formed the land of Cambodia.