What was the Marco Polo Bridge Incident?
Late on 7 July 1937 Japanese troops on night maneuvers near the Marco Polo Bridge (Lugouqiao), outside Peiping, now Beijing, clashed with Chinese troops of the 29th Army stationed at the bridge and in the walled town of Wanping. Each side blamed the other. Truces on 9 and 11 July broke down, Japan sent reinforcements, and by the end of July the Japanese held Peiping and Tientsin. The clash grew into a full-scale war between China and Japan.6
Nobody has ever proved who fired the first shot at the Marco Polo Bridge. What happened next is far better documented: within three weeks a night skirmish over a missing soldier had turned into a war that would last until 1945 and merge into the wider Pacific War. This article follows the incident day by day, from the night of 7 July to the fall of Peiping and Tientsin at the end of the month, and sets out what each side claimed.7
North China in the summer of 1937
Japan kept troops in North China under the Boxer Protocol of 1901, which let the powers guard their legations in Peking and twelve points on the railway to the sea. A supplementary agreement of 1902 allowed these troops to hold field exercises without informing the Chinese authorities, except when they fired live ammunition (feux de guerre). At the start of July 1937 the Japanese force there numbered about 7,000 by the League of Nations count, and 7,000 to 15,000 by the estimates the Tokyo war crimes tribunal cited later. The other powers had far smaller detachments.8
Japanese troops were stationed at Fengtai, a town just west of Peiping, as Peking (Beijing) was then called. The bridge at Lukouchiao (Lugouqiao), which Westerners called the Marco Polo Bridge, lay a little further on, southwest of the city: 13 kilometers (8 miles) away by the League of Nations count, 10 miles (16 km) by the US Embassy's and twelve miles (19 km) by Barbara Tuchman's. Next to it stood the small walled town of Wanping.9
The bridge mattered because of the railways. A Chinese Foreign Office official described Lukouchiao as the junction of three rail lines, and the Tokyo tribunal noted that whoever held the bridge could control Peiping from the west. Tuchman, the biographer of the American officer Joseph Stilwell, then military attaché in Peiping, called the railway there the only remaining access to the city not under Japanese control. The Japanese had repeatedly asked for the Chinese troops at Lukouchiao to be withdrawn.10
The Chinese troops in the region belonged to the 29th Army of General Sung Che-yuan (Song Zheyuan), who also chaired the Hopei-Chahar Political Council. Those at the bridge and in Wanping came from its 37th Division, commanded, according to both the US and the Japanese embassies, by General Feng Chih-an (Feng Zhian). Sung himself was away on leave at his home (in Shantung, for almost two months, the US Embassy noted).11
For about two weeks before the incident Japanese troops had held maneuvers near the bridge, and the Tokyo tribunal found that they did so every night. The League of Nations committee wrote that the frequency of these exercises disquieted the Chinese, and that the clash came "in an atmosphere of tension".12
The night of 7 July
On the evening of 7 July Japanese troops held a night maneuver near Lukouchiao, and that night shots were fired near the bridge. The US Embassy identified the unit as a company of the Japanese Embassy Guard, part of the Kawabe Brigade, which had come out from Peiping by way of Fengtai. The accounts disagree on the time. The US Embassy reported the clash as shortly before midnight and the Japanese Embassy put it at 11:40 p.m., but the Tokyo tribunal found that the Japanese had already telephoned the Chinese authorities about Chinese fire at about 10 p.m.13
In the Japanese version, Chinese troops of the 29th Army opened fire on the Japanese soldiers. The Japanese Embassy in Washington said the attack came "for no cause at all". It added that the detachment had stopped its maneuver and asked Fengtai for reinforcements, and that the soldiers carried so little live ammunition that they could not have started the fight.14
In the Chinese version, the Japanese reported that a soldier was missing and demanded entry into Wanping to search the town. When this was refused, they attacked it. Chinese officials added that the missing soldier had soon returned, and the Tokyo tribunal found that on 9 July the Japanese themselves told the Chinese he had been found.15
During the night the two sides agreed to look into the matter on the spot. Early on 8 July Chinese and Japanese officers went into Wanping to negotiate, and while they were there the fighting broke out again.16
8 July: fighting at Wanping
8 July. The accounts of the morning differ again. Chinese guards at the gates of Wanping told an American diplomat that the Japanese had begun firing on the town at about 3:30 a.m., killing or wounding some tens of soldiers and killing ten or more civilians. A Japanese assistant military attaché told the press that Chinese troops had opened fire again at about 5 a.m. and that the Japanese had to take measures of self-defense. The Tokyo tribunal found that a Japanese battalion attacked at about 5 a.m. near the bridge and that machine guns opened on Wanping at about 6.17
Through the day the Japanese besieged Wanping with mortar and artillery fire and pressed their demands, and the Chinese garrison refused them. The office of the Japanese military attaché announced that a Japanese lieutenant had been killed and several soldiers killed or wounded.18
The first reactions in the two capitals already pointed in opposite directions. In Tokyo, the Foreign Office told the American ambassador that "our military people seem to believe that the firing by Chinese troops which started the incident was not premeditated". In Nanking, a Chinese Foreign Office official called the incident "clearly premeditated by the Japanese".19
9 to 11 July: truces that did not hold
9 July. The local commanders agreed on a truce and a mutual withdrawal of troops. According to the US Embassy, foreign eyewitnesses saw the Chinese keep their part and pull back west of the Yungting (Yongding) River.20
10 July. Some 1,000 Japanese troops advanced again to the Wanping area, the US Embassy reported. The Japanese government said instead that on the night of 10 July the 29th Army broke the agreement and suddenly fired on Japanese troops.21
11 July. A local agreement was reached. A Japanese Embassy official in Peiping said it was signed at 8 p.m. and provided for an apology by officers of the 29th Army, the punishment of those responsible and guarantees against a repeat. The US Embassy named General Chang Tzu-chung (Zhang Zizhong), the Mayor of Tientsin, as the Chinese signatory.22
The same day the Japanese cabinet decided to reinforce the garrison in North China with units of the Kwantung Army in Manchuria and of the army in Korea, and to mobilize more units in Japan. Its statement called the incident, beyond any room for doubt, a premeditated armed anti-Japanese action by the Chinese side (our translation), while still declaring a policy of not enlarging the incident and seeking a local settlement.23
According to the Tokyo tribunal, the Japanese General Staff had decided on 10 July to send two brigades from the Kwantung Army, one division from Korea and three divisions from Japan, and stopped the mobilization at home on the night of 11 July after hearing that the Chinese had come to terms. A Japanese archive summary of the incident puts the outcome simply: the conflict was resolved at the local level for a time, but full-scale war broke out in the end.24
Nanking and Tokyo dig in
The Japanese government insisted on a local settlement made without the central Chinese government in Nanking, and, the League of Nations noted, warned Nanking against sending its troops north into Hopei. Meanwhile reinforcements kept arriving. By 12 July, according to Chinese reports cited by the League of Nations, the Japanese had more than 20,000 men and 100 aircraft around Tientsin and Peiping. The Chinese Embassy in Washington spoke of 200,000 troops by 15 July.25
Chiang Kai-shek answered in an address at Kuling (Lushan), the mountain summer resort, released by the Central News Agency under the date of 19 July (the Tokyo tribunal dates the speech to 17 July). He said China was ready to fight to the end if the limit of endurance was reached: "We are not seeking war. We are meeting attacks upon our existence." He set four minimum conditions: no settlement that infringed China's sovereignty and territorial integrity, no illegal change to the Hopei-Chahar Political Council, no removal of officials appointed by the central government under outside pressure, and no restrictions on the positions of the 29th Army.26
End of July: Peiping and Tientsin fall
Fresh clashes at Langfang, between Peiping and Tientsin, and at the Kwanganmen gate of Peiping, which the Tokyo tribunal dates to 25 and 26 July, led to open fighting. The Japanese Embassy blamed "successive acts of betrayal on the part of the Chinese troops" there.27
28 July. Early in the morning Japanese aircraft attacked Nanyuan, just outside Peiping, and fighting broke out around the city. The US Embassy later reported that the divisional commander General Chao Teng-yu (Zhao Dengyu) was killed at Nanyuan. That day, the Tokyo tribunal found, Chiang Kai-shek ordered Sung to fall back to Paoting, and that night, the US Embassy reported, Sung left Peiping with his troops.28
29 July. In Tientsin Japanese planes bombed Nankai University among other targets, and fighting went on for two days before the Chinese fell back south.29
By the end of July the Chinese troops had left the Peiping and Tientsin area and the Japanese held both cities. The Tokyo tribunal dates the capture of Peiping to 8 August, when Japanese troops under Kawabe Shozo paraded through its streets. In the second week of August fighting broke out at Shanghai, which became a second theater of the war.30
The war that followed lasted until 1945. Battles such as the Second Battle of Changsha in 1941 were still to come, and after the attack on Pearl Harbor the conflict became part of the Second World War in Asia and the Pacific.31
Who fired first?
Neither the League of Nations nor the US Embassy in Peiping tried to settle who fired the first shot. The League set the Chinese and Japanese versions side by side, and the embassy wrote in August 1937: "Presumably it will never be established whether a Japanese or a Chinese fired the shot which precipitated the fighting in the vicinity of Marco Polo Bridge".32
The embassy still placed the responsibility on the Japanese, because they held night maneuvers close to a Chinese garrison at a tense time and outside the zone the 1901 Protocol had set for foreign troops. It did not believe the clash had been deliberately planned by the Japanese military, but judged that they soon decided to use it as a pretext to extend their influence in North China.33
The Tokyo war crimes tribunal, sitting after Japan's defeat, treated the clash as the start of the second phase of a war that Japan had begun in Manchuria in 1931. It noted that in June 1937 Tojo Hideki, then chief of staff of the Kwantung Army, had proposed to "deliver a blow" to the Chinese government first.34
Historians remain divided. In a 2014 survey of Japanese research, the historian Duan Ruicong wrote that Chinese scholars almost unanimously conclude that the Japanese fired first, while most Japanese scholars regard the incident as accidental. A group of Japanese scholars blames Chinese Communists for the first shot, a theory criticized by the Japanese historians Hata Ikuhiko, Eguchi Keiichi and Yasui Sankichi. Duan thought the question would perhaps always remain a mystery.35
When did the war begin?
Japanese officials spoke of the North China Incident and later of the China Incident, a name the Tokyo tribunal called a false description of what was a war. Japanese historians, Duan Ruicong notes, still debate whether to count an "Eight-Year War" from July 1937 or a "Fifteen-Year War" from the Mukden Incident of September 1931.36
China long dated its War of Resistance from 7 July 1937, as an eight-year war. In January 2017 the government moved the official start to 18 September 1931, and the Ministry of Education ordered textbooks revised to match, making it a fourteen-year war.37
The Museum of the Chinese People's War of Resistance Against Japanese Aggression in Beijing marks the incident at the bridge as the beginning of the war, while the timeline at the entrance to its galleries runs from 1931 to 1945, noted Keith Huxen of the National WWII Museum. For the US State Department's historians, the clash of 7 July 1937 threw China and Japan into full-scale war, and the conflict that followed helped push the United States toward war with Japan. More on Japan's wars of that era is in our military history of Japan.38
