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.