PAVN, and the communist-backed Khmer Rouge (known as the Cambodian Civil War, 1967–1975) and in Laos between the US-backed government, the PAVN, and the communist-backed Pathet Lao (known as the Laotian Civil War or Secret War, 1959–1975). The Third Indochina War was a period of prolonged conflict following the Vietnam War, in which several wars were fought: The Cambodian–Vietnamese War began when Vietnam invaded Cambodia and deposed the genocidal Khmer Rouge regime. The war lasted from May 1975 to December 1989. The Sino-Vietnamese War was a short war fought in February–March 1979 between the People's Republic of China and the Socialist Republic of Vietnam. The Chinese launched a punitive expedition in revenge for the Vietnamese invasion of Cambodia, and withdrew a month later to prewar positions. Skirmishes along the border would continue until November 1991. After the triumph of the Pathet Lao, an anti-communist insurgency in Laos lasted until most Hmong insurgents surrendered in 2007, though some resistance cells remained active for several years after. Thailand, which supported the Lao insurgents, as well as the anti-Vietnamese forces in the Third Indochina War, fought a few skirmishes with Vietnam in 1984, and a short conflict with Laos in 1987. FULRO insurgency against Vietnam - United Front for the Liberation of Oppressed Races The Communist Party of Thailand fought an insurgency from 1965 to 1989. They received backing from Laos and Vietnam from 1975 to 1979 but were expelled from their bases and lost most of their supply lines after they sided with the Cambodian-Chinese aligned forces, rather than the pro-Soviet Vietnamese and Laotian regimes. Background French Indochina French colonization and occupation of the region was a consequence of missionary work of the 16th century, which had resulted in Catholics forming a converted minority. While Emperor Gia Long tolerated Catholicism, his successors Minh Mạng and were orthodox Confucians, admiring ancient Chinese culture. They forbade Catholic proselytism, as it was usually the religious arm of colonization and they resisted European and American attempts to establish colonial trade posts, which France tried to impose against the laws of the country. This was seen by colonial powers as "provocative". Confucian isolationist policy led the Vietnamese to refuse industrial modernization, so that they were not able to resist military power of a French invasion. In August 1858, Napoleon III ordered the landing of French forces at Tourane, (present-day Da Nang), beginning a colonial occupation that was