Souvanna Phouma was the son of Bounkhong, the last vice-king of Luang Prabang and a nephew of King Sisavang Vong of Laos, given a French education in Hanoi, Paris and Grenoble, where he obtained his degree in architecture and engineering.

In August 1956 Souvanna and the Communist Pathet Lao, which his half-brother Souphanouvong headed agreed on broad proposals for a 'government of national union'.

Elections for 21 extra assembly seats were finally held in May 1958, with parties aligned with the Pathet Lao acquiring 13.

283, approved a provisional government formed by Prince Boun Oum, who acted as front man for Phoui Sananikone.

He was one of the Three Princes, whom Sisavang Vatthana appointed to form a coalition government between the rightists and Pathet Lao but it collapsed, and the Laotian Civil War began.