History of Sino-Russian relations
Prior to the 17th century China and Russia were on opposite ends of Siberia, which was populated by independent nomads. By about 1640 Russian settlers had traversed most of Siberia and founded settlements in the Amur River basin. From 1652 to 1689, China's armies drove the Russian settlers out, but after 1689, China and Russia made peace and established trade agreements.
By the mid-19th century, China's economy and military lagged far behind the colonial powers. It signed unequal treaties with Western countries and Russia, through which Russia annexed the Amur basin and Vladivostok. The Russian Empire and Western powers exacted many other concessions from China, such as indemnities for anti-Western riots, control over China's tariffs, and extraterritorial agreements including legal immunity for foreigners and foreign businesses.
Issues that affected only Russia and China were mainly the Russian-Chinese border since Russia, unlike the Western countries, bordered China. Many Chinese people felt humiliated by China's submission to foreign interests, which contributed to widespread hostility towards the emperor of China.
In 1911, public anger led to a revolution, which marked the beginning of the Republic of China. However, China's new regime, known as the Beiyang government, was forced to sign more unequal treaties with Western countries and with Russia. In recent years, Russia and China signed a border agreement.
In late 1917, Moscow and Petrograd were taken over by a communist group, the Bolsheviks, during the October Revolution, which caused the Russian Civil War between the Bolshevik Red Army and the anticommunist White forces. China's Beiyang government sided with the Whites and, along with most of the West, sent troops to fight against the Reds. In 1922, the Reds won the civil war and established a new country: the Soviet Union. In 1923, the Soviets provided aid and support to the Kuomintang, a Chinese faction that had been opposed to the Beiyang government. In alliance with the small Chinese Communist Party (CCP), the Kuomintang seized power in 1928, and both countries established diplomatic ties. Sino–Soviet relations remained fractious, and both countries fought two wars for the next ten years. Nevertheless, the Soviets, under Joseph Stalin, helped Chiang Kai-shek's Kuomintang government against Imperial Japan. Stalin told the Communists' leader, Mao Zedong, to co-operate with China's Kuomintang regime, but Mao attacked the Kuomintang anyway. The communists failed to overthrow Chiang's government.
In 1937, the Kuomintang and the communists formed a new alliance to oppose the Japanese invasion of China, but they resumed fighting each other in 1942. After Japan had been defeated in 1945, both Chinese factions signed a truce, but the Chinese Civil War soon erupted again between them.
In 1949, with Soviet support, the communists won the Chinese Civil War and established the People's Republic of China, which made an alliance with the Soviets. Mao became the first leader of Communist China. Mao's most radical supporters, who became known as the "Gang of Four," gradually eliminated most of his rivals throughout his 27 years in power.
Ideological tension between the two countries emerged after Stalin's death in 1953. Nikita Khrushchev denounced Stalin's crimes in 1956, and both regimes started to criticise each other. At first, the criticism was indirect and muted, but in 1961, Mao accused the Soviet leadership of revisionism, and the alliance openly ended. Both countries competed for control over foreign communist states and political movements, and many countries had two rival communist parties that concentrated their fire on each other.
In 1969, a brief border war between the two countries occurred. Khrushchev had been replaced by Leonid Brezhnev in 1964, who abandoned many Soviet reforms criticized by Mao. However, China's anti-Soviet rhetoric intensified under the influence of Mao's closest supporters, the Gang of Four. Mao died in 1976, and the Gang of Four lost power in 1978.
After a period of instability, Deng Xiaoping became the new leader of China. The philosophical difference between both countries lessened somewhat since China's new leadership abandoned anti-revisionism.
China's internal reforms did not bring an immediate end to conflict with the Soviet Union. In 1979, China invaded Vietnam, which was a Soviet ally. China also sent aid to the mujahedin against the Soviet invasion of Afghanistan. In 1982, Brezhnev made a speech offering reconciliation with China, and Deng agreed to restore diplomatic relations.
In 1985, Mikhail Gorbachev became President of the Soviet Union, reduced the Soviet garrisons at the Sino–Soviet border and in Mongolia, resumed trade, and dropped the border issue that had caused open war 16 years earlier. In 1989, he withdrew Soviet support from the communist government of Afghanistan. Rapprochement accelerated after the Soviet Union fell and was replaced by the Russian Federation in 1991.