Wikipedia
Samsenethai (also called Oun Huan) was the second king of Lan Xang, the son of Fa Ngum, whom he succeeded.
He ruled from 1372 until 1417. The origin of the name Samsenethai is thought to be a reflection of the political and social upheaval occurring within the area at the time of his rule. Samsenethai literally means "300,000 Thai," thus reflected the result of a census conducted in his reign. It is unclear whether the census included the entire population or just men capable of bearing arms.
There is also discussion as to whether during this period, the terms "Thai" and "Lao" were interchangeable, whether the term "Lao" yet existed, or whether "Thai" was used in his name to refer to the fact that the census included all Tai groups. Local Thai history records that Samsenethai's Mother was a high born lady of Ayuttaya (Siam - Thailand) and that she had brought Thai Ministers for the government of Lan Xiang (Lan Chiang). Also noteworthy, the flag adopted for Lan Xiang is a near copy of the flag of Ayuttaya. Red background with a White elephant in the center. For the duration of his 43-year reign, Lan Xang did not fight a single battle.
Samsenethai had five daughters; Princess Keo Koumari, Princess Anousa, Princess Manôra, Princess Souphutta, and Princess Siva Yaka. He had three sons by Princess Ngo Fa of Ayutthaya; Prince Lan Kham Deng, Prince Sai, Prince Khamtèm. His other sons, Prince Kongkèo, Prince Lu Xay, and Prince Fa Kheun's mother was Princess Noy Onsa of Lan Na.
Wat Manorom, Wat Oubôsôt, and Wat Xiang Kham were built in Samsenethai's reign. He was succeeded by his son Lan Kham Deng.