In 1950 the Meo (Hmong) ethnic group, Mr. Sia Ying Vue as Nai Kong (mini district chief), the refugee leader, Tasseng (county chief) Navang, Muong (province-state-district) Vangsai, Xiangkhouang Province, lived in Sam Thong[4] with other ethnic groups.

During this period, particularly in early 1962, US forces established a refugee operation center in Sam Thong.

[2] The town was attacked by People's Army of Vietnam forces in March 1970 as part of Campaign 139, causing US personnel and their allies to withdraw.

[6] Following the end of the Laotian Civil War in 1975, Sam Thong became part of the socialist Lao People's Democratic Republic.In 1949 the governor of Xiangkhouang province was Chao Saykham Southakakoumane.

In December 1960, when Kong Le and his troops captured the Plain of Jars and Phonsavan, General Vang Pao and Xiangkhouang Governor Chao Saykham[8] decided to settle in Sam Thong in 1962.

Sam Thong[10] became Xiengkhouang's main social-military-administrative office center during the CIA secret War.

Besides Sam Thong, its neighbor was Long Tieng, where the US Central Intelligence Agency military was stationed during the Vietnam War of 1961–1975.

In Sam Thong there was not only the governor, the police, Chao Muong (district chief), Nai Ban (village chief) and those of the school offices, there was also a public and military hospital of 150-beds[15] built and equipped at Sam Thong in Xiengkhouang province which[16][17] was called San Sook (Lao: ແສນສຸກ) and was the largest hospital[18] serving all of northeaster Laos, especially in Xiangkhouang Province at the time.

No matter what mathematics, geography, history, and others are, the system of the secondary education in Laos was almost part in French language, especially in middle and high schools.

Sam Thong middle high school was ranked the highest one in Xiangkhouang province, due to its teaching classes of 6th B, 6th A, 5th, 4th, and 3th (grade 9th).

It was then that he was replaced by Maxime Lesage, a Frenchman of Puducherry (union territory) origin, as principal starting 1971/72 school year.

Thus, Sam Thong college's students fled their homes with their families to refugee camps in Thailand to seek political asylum.

After the Vietnam war most of the students of this middle high school, especially the Sam Thong college, left their hometown to flee the country, which was Laos, with their parents to go to western countries which are the United States for the most part, then to France, Australia and Canada.