Under the influence of the October Revolution in Russia, China's May 4th Movement arose. During this great anti-imperialist, anti-feudal revolutionary movement led by patriotic students, the Chinese proletariat for the first time mounted the political stage. The May 4th Movement marked the change of the old democratic revolution to the new democratic revolution. It enabled Marxism-Leninism to further spread and link up with the Chinese people's revolutionary practice, and prepared the ideology as well as the cadres necessary for the founding of the Communist Party of China. In 1921, Mao Zedong, Dong Biwu, Chen Tanqiu, He Shuheng, Wang Jinmei, Deng Enming and Li Da, representing the communist groups in different places throughout the nation, held the First National Congress in Shanghai, founding the Communist Party of China (CPC). In 1924, Sun Yat-sen, pioneer of China's democratic revolution and the founder of the Kuomintang (KMT), worked together with the Communist Party of China to organize workers and peasants for the Northern Expedition (historically known as the Great Revolution). After Sun Yat-sen passed away, the right-wing clique of the KMT headed by Chiang Kai-shek staged a counter-revolutionary coup d'etat in 1927, murdering Communists and revolutionary people, and founded the Kuomintang regime in Nanjing. Thus the Great Revolution ended in failure. After that, the CPC led the Chinese people to wage the 10-year Agrarian Revolution War against the reactionary rule of the Kuomintang, which is also known as the "10-Year Civil War."
In July 1937, Japan launched all-out aggression against China. The Kuomintang armies started a series of battles, which gave relentless blows at the Japanese invaders. In the enemy's rear area, the Eighth Route Army and the New Fourth Army, under the leadership of the CPC, fought against most of the Japanese forces, and almost all the puppet armies under extremely difficult conditions, thus playing a decisive role in the victory of the War of Resistance Against Japan.
From June 1946, the Kuomintang armies launched an all-round attack on the Liberated Areas led by the CPC, and an unprecedented large-scale civil war started. To thoroughly emancipate the Chinese people, the CPC led the army and people in the Liberated Areas to start the nationwide War of Liberation.
Through the Liaoxi-Shenyang, Huai-Hai and Beiping-Tianjin campaigns, the CPC overthrew the rule of the Kuomintang and won a great victory in the new democratic revolution in 1949.