Relations between the People's Republic of China and the Soviet Union underwent significant change from 1969 to 1991, from open conflict to bitter détente to diplomatic partners by 1989. Relations between the Soviet Union (USSR) and Chinese Communist Party (CCP) dated back to the founding of the CCP in Shanghai in 1921, a meeting conducted under the supervision of the Communist International. The Soviets remained cautious partners with the rising CCP throughout the 22 years of the Chinese Civil War, and the USSR was the first nation to recognize the People's Republic of China in 1949. The following year saw the signing of the Sino-Soviet Treaty and founding of the Sino-Soviet alliance as well as the beginning of a decade of economic cooperation between the two nations.

Despite transfers of aid and raw materials between the nations, by 1956 this once warm friendship had cooled, and the Sino-Soviet split began. In 1960, the Soviet Union withdrew all economic advisors from the PRC, and relations became confrontational in political, economic, military and ideological arenas. After years of border incursions by both parties, 1969 saw the Sino-Soviet border conflict which nearly boiled over into a nuclear exchange.

After the Sino-Soviet border conflicts of 1969, Sino-Soviet relations were marked by years of military and political tensions. Even after the death of Mao Zedong in 1976, these two former allies remained locked in a miniature cold war, consumed by ideological, political and economic differences. However, relations began to improve in the late 1970s with a gradual de-escalation of military tensions and a move towards bilateral relations. After years of negotiations, full bilateral relations resumed in May 1989 in the midst of the 1989 Tiananmen Square protests and massacre. Warmer bilateral relations and mutual understanding would characterize the last two years of the Sino-Soviet relationship, up until the dissolution of the Soviet Union in December, 1991."In the 1950s the Soviet Union was "big brother," whose example should be followed. Through almost the entire two decades of the 1960s and 1970s, the Soviet Union became synonymous with "revisionism," the dreaded fate that China must avoid at all costs. Finally, in the 1980s, such extremes were avoided. The Soviet Union came to represent the common starting point for socialism, from which China and other socialist countries (the Soviet Union included) must shift, in steps, through carefully planned reforms." - Gilbert RozmanThe entire Sino-Soviet relationship was a roller coaster of events, from close alliance to nuclear showdown, but by the 1980s common approaches to reform enabled the resumption of diplomatic relations and extensive trade. These events spanned multiple generations of political leadership; Mao Zedong, Hua Guofeng and Deng Xiaoping led China, while Joseph Stalin, Nikita Khrushchev, Leonid Brezhnev, Yuri Andropov, Konstantin Chernenko, and Mikhail Gorbachev led the Soviet Union. Despite numerous domestic and foreign concerns, each generation of leadership devoted significant time and resources to the Sino-Soviet relationship, a relationship bound by political, economic, geographical, and ideological considerations.

Sino-Soviet Relations 1949 - 1969

Sino-Soviet Alliance

The Sino-Soviet Alliance began with the signing of the new Sino-Soviet Treaty of Friendship, Alliance and Mutual Assistance on February 14, 1950. Following the signing of this treaty, the USSR advanced $300 million in development loans to the PRC and sent nearly 10,000 Soviet technical advisors to work in China. Over the next decade, extensive technological transfer and development assistance drew the two countries close together, while China firmly allied with the Soviet Union in the Cold War.

Sino-Soviet split

However, for numerous reasons, the Sino-Soviet alliance weakened in the late 1950s, and the Soviet Union withdrew all economic aid in August 1960. The Sino-Soviet split began once minor political, economic, geographic and ideological issues became major bilateral diplomatic concerns.

Sino-Soviet Border War of 1969

Military Build-up

With the intensification of the Sino-Soviet Split, both nations deployed troops to the shared border, which stretched from North Korea to Central Asia. However, for the first part of the Sino-Soviet confrontation, the Mongolian People's Republic, a Soviet satellite since 1921, remained relatively neutral, and facilitated continued trade between the USSR and PRC. This changed with the signing of "The Treaty of Friendship, Cooperation and Mutual Assistance between the USSR and the Mongolian People's Republic" which superseded previous agreements of economic cooperation between the allied communist nations. The treaty, signed in Ulaanbaatar on January 15, 1966, by Soviet leader Leonid Brezhnev and Mongolian Prime Minister Yumjaagiin Tsedenbal, allowed the Soviet Union to station troops in Mongolia to ensure mutual defense. While the Soviet Army had previously operated in Mongolia, this was the first time that troops would be based in the independent nation. By 1967, the Soviet Union had deployed armored units and mechanized troops as well as ballistic missiles inside Mongolia and along the Chinese border. Border incidents and clashes continued to increase with 4,189 border crossing incidents between 1964 and 1969. The border conflict grew worse as each side moved more troops into the borderlands, and tensions in Moscow and Beijing rose to a breaking point.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 250. These developments along the northern border put Mao into a potential two front war, what Mao called "[A] new historical epoch of combating both U.S. imperialism and Soviet revisionism" in a letter to Enver Hoxha in September 1968. This letter, reprinted in the People's Daily, September 19, 1968, illustrated the brewing potential for a trilateral nuclear war.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 285.

Two Front Border Conflict (February - August 1969) In this environment of nuclear showmanship and military tensions, the Chinese side made the first move. In 1969, the Chinese People's Liberation Army (PLA) attacked Soviet Border Guards stationed on Zhenbao Island in the Ussuri River, claiming the island for China. In repeated attacks and counterattacks up to 250 Chinese soldiers and 58 Soviet soldiers were killed.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 251. In the aftermath, both sides withdrew leaving the island as no-mans-land subject to frequent artillery barrages. The PLA argued that such attacks would not lead to a wider war with the Soviet Union, but China's leadership still prepared for war. The Soviet Union responded with thinly veiled threats of nuclear war if attacked again and counter-attacked on the western border. Minor clashes continued throughout the summer. On August 13, 1969, the Soviet Army invaded Yumin County in Xinjiang, eliminating the PLA platoon in the area.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 254. In addition, the Soviets transferred strategic nuclear bombers to airbases in the Russian Far East within striking distance of Manchurian nuclear facilities.

What had started as a border skirmish threatened to become a two front nuclear war. The PRC reacted by further preparing for war along the borderlands, while also seeking to reduce tensions in a high-level meeting with Soviet leaders.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 255. Premiers Alexei Kosygin and Zhou Enlai met at the Beijing Airport on September 11, 1969, and through a hurried series of meetings attempted to carefully negotiate a step-back from the brink of war. Further letters between the two premiers sought to de-escalate tensions but neither side withdrew troops from the border. However, the sides agreed to meet on October 20 in Beijing to solve the border-dispute diplomatically.Khoo, Collateral Damage, 59.

Mao Zedong and Lin Biao feared that the Soviet negotiations were a trick, a ploy to draw off Chinese troops while the Soviets would attack with ground and nuclear forces. Under orders from Mao, Lin Biao put the PLA strategic forces on war-readiness in full preparation for a nuclear war with the Soviet Union.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 256. What had begun as a diplomatic attempt to calm tensions, instead resulted in nuclear brinkmanship.Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 257. With the nation on full alert, civilian and military authorities began to prepare for total war, under the premise that the arrival of a Soviet border negotiations team would be a ruse for an all-out nuclear strike.Khoo, Collateral Damage, 60. Yet, no strike came; on October 20, the Soviet diplomats arrived and border tensions settled for the time being.

Tensions and Sino-American Relations 1969 - 1978

Sino-US rapprochement, a major break with previous foreign policies seeking to create a new balance of power in East Asia, greatly affected the Sino-Soviet relationship. Threatened by the potential of a crippling Soviet attack, China turned to the United States. While visiting China, American President Richard Nixon and National Security Advisor Henry Kissinger worked to allay Chinese fears of a joint US-Soviet attack and instead promote ties with China that would undermine the Soviet Union. Li Danhui and Xia Yafeng argue that Mao Zedong's ideological shift toward Sino-US relations was heavily influenced by the continuing threat of the USSR. Pivoting away from military confrontation, Mao declared a policy of "opposing the Soviet Union, irrespective of ideological position."Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 260. This opened the door for continued cooperation and negotiation with the United States and cooperation balancing against Soviet power in East Asia. According to historian Li Danhui, "after the Zhenbao Island Incident in March 1969, the Sino-Soviet state-to-state relationship was on the brink of war. This prompted Mao to attempt a new policy of aligning with the United States to oppose the Soviet Union."Li; Xia. Mao and the Sino-Soviet Split 1959-1973, 282.

In the midst of Sino-American reproachment in 1972, the Sino-Soviet border continued to be heavily fortified, with nearly 1 million Soviet troops, armed with tanks, airplanes, artillery and backed by ballistic missiles. The Soviet Army faced approximately 1.5 million troops consisting of the PLA and People's Militia. The border tensions increased from 1973 through 1976, as both sides sought political victories while also continuing to militarize the border. Brezhnev spoke of China's failure to accept peaceful coexistence between the two nations, while the PRC continued to view the Soviet Union as an existential threat.Khoo, Collateral Damage, 80. The presence of the Soviet Navy in the Indian and Pacific oceans as well as well-armed troops across the length of the border reinforced a view of Soviet encirclement.Khoo, Collateral Damage, 81.

The death of Mao in September 1976 brought no immediate changes in the Sino-Soviet conflict, although each side had significantly reduced the number of troops stationed along the border. Brezhnev attempted to congratulate Hua Guofeng in October 1976, and was strongly rebuffed with a reinforcement of the late chairman's anti-Soviet rhetoric.Khoo, Collateral Damage, 110. In 1976, each side had approximately 300,000 soldiers deployed on the border, while the Soviet troops were backed by airpower and strategic forces.Khoo, Collateral Damage, 104. In 1978, the Soviets began deploying SS-20 missiles throughout the Far East, allowing them to strike any target in the PRC. In addition, large military exercises were performed in both Mongolia and Siberia, specifically modelling different scenarios of a Sino-Soviet war.Khoo, Collateral Damage, 107.

Sino-Vietnam War 1979