This city was founded by the French as an administrative outpost in 1905, and was formerly the capital of the Lao Kingdom of Champasak until 1946 when the Kingdom of Laos was formed. During the Franco-Thai war the French ceded Pakse to Thailand. The city served as the primary seat and residence to Prince Boun Oum Na Champassak, an important figure in the Laotian Civil War. He built Champasak Palace, but fled in 1974 before it was completed. In May 1975, it fell to Pathet Lao forces. Since 1975, Pakse has become an economic power and of regional importance within the region. The construction of a bridge over the Mekong, built with Japanese aid, allowing road traffic with Ubon Ratchathani in Thailand, has further integrated the city with neighbouring countries.