Chiang Kai-shek’s April 12, 1927 coup against the Communists.

Further reading:
Steve Smith, A Road Is Made: Communism in Shanghai, 1920-1927
Elizabeth Perry, Shanghai on Strike: The Politics of Chinese Labor
Maurice Meisner, Li Ta-chao and the Origins of Chinese Marxism
Stuart Schram, ed., Mao’s Road to Power, vol. 3: From the Jinggangshan to the Establishment of the Jiangxi Soviets, July 1927-December 1930

Some names from this episode:
Wang Shouhua, President of the General Labor Union
Du Yuesheng, One of three top leaders of the Green Gang
Huang Jinrong, One of three top leaders of the Green Gang (and top cop in the French Concession)
Zhou Enlai, Leading Communist responsible for the workers’ armed forces in Shanghai
Bai Chongxi, NRA commander whose forces occupied Shanghai
Li Dazhao, Co-founder of the Communist Party
Gregory Voitinsky, Chairman of the Far Eastern Bureau of the Comintern

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