One of the most important battles of the Second Sino-Japanese War – despite relatively low casualties – the Marco Polo Bridge Incident flared up on July 7, 1937, directly leading to Japan’s occupation of Tianjin and Wanping (today part of Beijing’s Fengtai District). It is generally regarded as the ‘official’ start of China’s resistance against Japanese aggression.
The Japanese army controlled the north, east and south sides of Beijing, but the Marco Polo Bridge remained in Chinese hands.
In order to cut off Beijing entirely, Japan needed control of the bridge. Thus they manufactured a provocation that could be used to justify an escalation of hostilities.
The army held a military exercise without informing Chinese authorities, during which, according to an intelligence officer, a Japanese soldier was reported missing after gunshots were heard. The Japanese used this as a reason to enter Wanping to search for the AWOL soldier – which China refused.
At about 5am on July 8, the Japanese launched an artillery attack and both sides joined battle, with the fight soon taken to Tianjin; the city was captured at the end of July.
The incident marked the second instance of cooperation between the Communist Party and Kuomintang (KMT) forces. The anti-Japanese National United Front was formed, with the Red Army rebranded the Eighth Route Army and the New Fourth Army of the KMT.
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