Vietnam was an ideological battleground of the
Sino-Soviet split of the 1960s. After the
Gulf of Tonkin incident in 1964, Chinese Premier
Deng Xiaoping secretly promised the North Vietnamese 1 billion
yuan in military and economic aid, on the condition that they refused all Soviet aid.
During the Vietnam War, the North Vietnamese and the Chinese had agreed to defer tackling their territorial issues until South Vietnam was defeated. These issues included the lack of delineation of Vietnam's territorial waters in the
Gulf of Tonkin, and the question of sovereignty over the
Paracel and
Spratly Islands in the
South China Sea.
[1] During the 1950s, half of the Paracels were controlled by China and half by South Vietnam. In 1958, North Vietnam accepted China's claim to the Paracels, relinquishing its own claim;
[22] one year earlier, China had ceded
White Dragon Tail Island to North Vietnam.
[23] The potential of offshore oil deposits in the Gulf of Tonkin heightened tensions between China and South Vietnam. In 1973, with the Vietnam War drawing to a close, North Vietnam announced its intention to allow foreign companies to explore oil deposits in disputed waters. In January 1974, a
clash between Chinese and South Vietnamese forces resulted in China taking complete control of the Paracels.
[1] After its absorption of South Vietnam in 1975, North Vietnam
took over the South Vietnamese-controlled portions of the Spratly Islands.
[1] The unified Vietnam then canceled its earlier renunciation of its claim to the Paracels, while both China and Vietnam claim control over all the Spratlys, while both controlling portions of the island group.
[22]
Main article:
Sino-Vietnamese War
In the wake of the Vietnam War,
Vietnam's 1978 invasion and occupation of Cambodia provoked tensions with China, which had allied itself with the
Democratic Republic of Kampuchea.
[1][24] This, and Vietnam's close ties to the Soviet Union, made China consider it a threat to its regional sphere of influence.
[24][25] Tensions were furthermore heightened in the 1970s by the Vietnamese government's oppression of the
Hoa minority, which consists of Vietnamese of Chinese ethnicity.
[1][24][25] By 1978, China ended its aid to Vietnam, which had signed a treaty of friendship with the Soviet Union, establishing extensive commercial and military ties.
[1][24]
On February 17, 1979, the Chinese
People's Liberation Army crossed the Vietnamese border, withdrawing on March 5 after a two-week campaign which devastated northern Vietnam and briefly threatened the Vietnamese capital,
Hanoi.
[1][25] Both sides suffered relatively heavy losses, with Chinese casualties put at over 10,000 and Vietnamese casualties at over 30,000. Subsequent peace talks broke down in December 1979, and both China and Vietnam began a major build-up of forces along the border. Vietnam fortified its border towns and districts and stationed as many as 600,000 troops; China stationed approximately 400,000 troops on its side of the border.
[25] Sporadic fighting on the border occurred throughout the 1980s, and China threatened to launch another attack to force Vietnam's exit from Cambodia.
[1][25]
http://en.wikipedia.org/wiki/China%E2%80%93Vietnam_relations