7th July 1937: Marco Polo Bridge Incident acts as a trigger for the Second Sino-Japanese War

**Scott Allsop** (0:00)
On 7th July 1937, the Marco Polo Bridge incident acted as a trigger for the second Sino-Japanese War. Welcome to HistoryPod.
Japan significantly expanded its influence in northern China during the 1930s. Following the Mukden incident and the subsequent occupation of Manchuria, Japan had established the puppet state of Manchukuo. Japanese forces maintained a military presence around Beijing under early agreements, while the Chinese government of Chiang Kai-shek sought to avoid a confrontation as it continued to deal with political divisions and the ongoing Chinese civil war. On the night of 7th July, Japanese troops conducted a routine training exercise near the Marco Polo Bridge on the outskirts of Beijing. After this exercise, one Japanese soldier was briefly reported missing, and Japanese commanders demanded permission to enter the nearby walled town of Wanping to search for him. Chinese forces refused the request regarding it as a violation of their sovereignty, and although the missing soldiers soon returned safely, tensions had already escalated and exchanges of gunfire broke out between the two sides, with each blaming the other for firing first.
Although local commanders attempted to negotiate temporary ceasefires, reinforcements were soon sent into the area by both governments. Over the next few days, fighting intensified and spread beyond the bridge. Diplomatic efforts failed to contain the crisis, and by the end of July, major battles had begun around Beijing and Tianjin. What had begun as a local military incident therefore developed into the Second Sino-Japanese War and which later became part of the wider Second World War in Asia. Although often overshadowed by events in Europe, the fighting that began on 7th July 1937 therefore marked one of the earliest major conflicts of the Second World War.