The 8th century Thai locality of Muang Then is believed to have been centered here.
Operation Castor (1953)
In the 1950s, the town was known not only for its famous opium traffic, generating 500,000,000 French francs annually, but more so for a fierce battle that would result in a major realignment of world geopolitics. It was also an extensive source of rice for the Việt Minh.
The region was fortified in November 1953 by the French Union force in the biggest airborne operation of the 1946-1954 First Indochina War, Operation Castor, to block Việt Minh transport routes and to set the stage to draw out Việt Minh forces.
Siege of Điện Biên Phủ (1954)
The following year, the important Battle of Điện Biên Phủ was fought between the Việt Minh (led by General Võ Nguyên Giáp), and the French Union (led by General Henri Navarre, successor to General Raoul Salan). The siege of the French garrison lasted fifty-seven days, from 17:30, 13 March to 17:30, 7 May 1954. The southern outpost or fire base of "Camp Isabelle" did not follow the cease-fire order and fought until 01:00, a few hours before the long-scheduled Geneva Meeting's Indochina conference involving the United States, the UK, the French Union and the USSR.
The battle was significant beyond the valleys of Điện Biên Phủ. Giáp's victory ended major French involvement in Indochina and led to the accords which partitioned Vietnam into North and South. Eventually, these conditions inspired the United States to increase their involvement in Vietnam leading to the Second Indochina War.
The battle of Điện Biên Phủ is described by historians as "the first time that a non-European colonial independence movement had evolved through all the stages from guerrilla bands to a conventionally organized and equipped
