The traditional court histories of Lan Xang begin in the "Year of the Nāga" 1316 (the nāga a mythical serpent of the Mekong and a protector spirit of the kingdom) with the birth of Fa Ngum. Fa Ngum's Grandfather Souvanna Khampong was king of Muang Sua and his father Chao Fa Ngiao was the crown prince. As a youth Fa Ngum was sent to the Khmer Empire to live as a son of King Jayavarman IX, where he was given princess Keo Kang Ya. In 1343 King Souvanna Khampong died, and a succession dispute for Muang Sua took place.