Shanghai massacre

The Shanghai massacre of 12 April 1927, the April 12 Purge or the April 12 Incident as it is commonly known in China, was the violent suppression of Chinese Communist Party (CCP) organizations and leftist elements in Shanghai by forces supporting General Chiang Kai-shek and conservative factions in the Kuomintang (Chinese Nationalist Party or KMT). The event began the campaign of anti-communist repression in Nationalist China.

Following the incident, conservative KMT elements carried out a full-scale purge of communists in all areas under their control, and violent suppression occurred in Guangzhou and Changsha. The purge led to an open split between left-wing and right-wing factions in the KMT, with Chiang Kai-shek establishing himself as the leader of the right-wing faction based in Nanjing, in opposition to the original left-wing KMT government based in Wuhan, which was led by Wang Jingwei.

By 15 July 1927, the Wuhan regime had expelled the CCP from its ranks, effectively ending the First United Front, a working alliance between the KMT and the CCP under the tutelage of Communist International (Comintern) agents. For the rest of 1927, the CCP would fight to regain power, beginning the Autumn Harvest Uprising and culminating with the Nanchang uprising, nominally commencing the Chinese Civil War. With the failure and the crushing of the Guangzhou Uprising however, the power of the CCP was largely diminished, unable to launch another major urban offensive for years.

In KMT historiography, the event is occasionally referred to as the April 12 Purge (simplified Chinese: 四一二清党; traditional Chinese: 四一二清黨; pinyin: Sìyī'èr Qīng Dǎng; Wade–Giles: Ssu⁴-i¹-erh⁴ Ch'ing¹ Tang³), while Communist historiography refers to the event as either the April 12 Counter-revolutionary Coup (simplified Chinese: 四一二反革命政变; traditional Chinese: 四一二反革命政變; pinyin: Sìyī'èr Fǎngémìng Zhèngbiàn; Wade–Giles: Ssu⁴-i¹-erh⁴ Fan³-ko²-ming⁴ Cheng⁴-pien⁴) or the April 12 Massacre (Chinese: 四一二慘案; pinyin: Sìyī'èr Cǎn'àn; Wade–Giles: Ssu⁴-i¹-erh⁴ Ts'an³-an⁴).

The April 12 Incident is rooted in the Kuomintang's alliance with the Soviet Union, formally initiated by the KMT founder Sun Yat-sen after discussions with Soviet diplomat Adolph Joffe in January 1923. The alliance included both financial and military aid as well as a small but important group of Soviet political and military advisors headed by Mikhail Borodin. The Soviet Union's conditions included co-operation with the small Chinese Communist Party. Sun agreed to let the Communists join the KMT as individuals but ruled out an alliance with them or their participation as an organized bloc. In addition, he demanded that the Communists, upon joining the KMT, adhere to KMT ideology and observe party discipline. Following their admission to the KMT, Communist activities, often covert, soon attracted opposition to the alliance among prominent KMT members. Internal conflicts between left- and right-wing leaders of the KMT with regards to the United Front with the CCP continued right up to the launch of the Northern Expedition.^{[citation needed]}

Plans for a Northern Expedition originated with Sun Yat-sen. After his expulsion from the government in Peking, he had, by 1920, made a military comeback and gained control of parts of Guangdong province. His goal was to extend his control over all of China, particularly Peking. After Sun's death from cancer in March 1925, KMT leaders continued to push the plan, and after they had purged Guangzhou's Communists and Soviet advisors during the "Canton Coup" on 20 March 1926, they finally launched the Expedition that June. Initial successes in the first months of the Expedition soon saw the KMT National Revolutionary Army (NRA) in control of Guangdong and large areas in Hunan, Hubei, Jiangxi, and Fujian.^{[citation needed]}

With the growth of KMT authority and military strength, the struggle for control of the Party's direction and leadership intensified. In January 1927, the NRA, commanded by Chiang Kai-shek, captured Wuhan and went on to attack Nanchang, and KMT leader Wang Jingwei and his left-wing allies, along with the Chinese Communists and the Soviet agent Borodin, transferred the seat of the Nationalist Government from Guangzhou to Wuhan. On 1 March, the Nationalist government reorganized the Military Commission and placed Chiang under its jurisdiction while it secretly plotted to arrest him. Chiang found out about the plot, which most likely led to his determination to purge the CCP from the KMT.

In response to the advances of the NRA, Communists in Shanghai began to plan uprisings against the warlord forces controlling the city. On 21–22 March, KMT and CCP union workers, led by Zhou Enlai and Chen Duxiu, launched an armed uprising in Shanghai and defeated the warlord forces of the Zhili clique. The victorious union workers occupied and governed urban Shanghai except for the international settlements prior to the arrival of the NRA's Eastern Route Army, led by Generals Bai Chongxi and Li Zongren. After the Nanking Incident in which foreign concessions in Nanjing were attacked and looted, both the right wing of the Kuomintang and Western powers became alarmed by the growth of the influence of the Communists, who continued to organize daily mass student protests and labor strikes to demand the return of Shanghai international settlements to Chinese control. With Bai's army firmly in control of Shanghai, on 2 April the Central Control Commission of KMT, led by former Chancellor of Peking University Cai Yuanpei, determined that the CCP actions were anti-revolutionary and undermined the national interest of China, and it voted unanimously to purge the Communists from the KMT.^{[better source needed]}