On the night of 7 July 1937 Japanese troops on night maneuvers near the Marco Polo Bridge (Lugouqiao), southwest of Beiping, now Beijing, clashed with the Chinese garrison of the walled town of Wanping. Nobody has ever proved who fired first. Neither government would back down, and within weeks the local skirmish had become a full-scale war between China and Japan, the conflict that in December 1941 merged into the Pacific war.
North China in 1937
Japan had seized Manchuria in 1931 and set up the puppet state of Manchukuo, and over the following years it pushed its control into northern China around Beiping and Tianjin. The pressure fed a growing anti-Japanese movement in China. In December 1936 the Xi'an Incident forced Chiang Kai-shek's Nationalists into a United Front with the communists against Japan.1
Before the incident the Japanese army already held Fengtai, a railway junction close to the Marco Polo Bridge southwest of the city, and its troops had held exercises there as well.2
A shot in the dark
Late on the evening of 7 July a small Japanese force was holding maneuvers near the bridge. It demanded entry to Wanping to search for one of its soldiers, and the Chinese garrison refused. Shots were fired and the two sides began shooting at each other.3
The accounts of that night still differ. A despatch from the U.S. embassy in Peiping, dated 17 August 1937, set the two versions side by side. The Japanese assistant military attaché said Chinese troops had suddenly fired on Japanese soldiers and that Japan had acted in self-defense; the mayor of Peiping said the Japanese reported being fired on and a soldier missing, were refused entry to Wanping, and that the missing soldier later returned. The despatch concluded that it would presumably never be established whether a Japanese or a Chinese soldier fired the first shot.4
The embassy still put the responsibility on Japan: its troops had held night maneuvers close to a regular Chinese garrison at a time of high tension, carrying live ammunition, in an area outside the zone where foreign troops were allowed to move under the 1901 Protocol. It did not believe the Japanese army had planned the clash, but it judged that Japan quickly decided to use it as a pretext to extend its influence in North China.5
From incident to war
Britannica writes that the Chinese government, under strong anti-Japanese pressure, refused to make concessions, and the Japanese held their position too, so the conflict kept growing. The Office of the Historian of the U.S. State Department describes the clash as throwing the two nations into a full-scale war. According to Britannica, Beiping and Tianjin were occupied in July 1937, the Chinese armies were driven out of the Shanghai area by the middle of November, and the Nationalist capital Nanjing fell in mid-December.6
Japan hoped for a quick victory and did not get one. The war in China went on until 1945 and, after Pearl Harbor, became part of the Pacific war; that story is told in our article on the attack on Pearl Harbor and our guide to the greatest battles of the Pacific war.7
Where the war began is itself a question of memory. Keith Huxen of The National WWII Museum notes that China's museum of the War of Resistance commemorated 7 July 1937 as its start, and that the Chinese government later moved the official beginning back to 18 September 1931, the Mukden Incident.8
