Marco Polo Bridge Incident (Battle of Lugou Bridge)

From June 1937, Japanese troops carried out intensive military training maneuvers in the vicinity of the western end of the Marco Polo Bridge. These were held every night (other foreign garrison troops seldom held night maneuvers), and the Chinese government requested that advance notice be given so that local inhabitants would not be disturbed. The Japanese agreed to this condition. However, on the night of July 7, 1937, night maneuvers were carried out without prior notice, greatly alarming the local Chinese forces. Chinese troops, thinking an attack was underway, fired a few ineffectual rifle shots, leading to a brief exchange of fire at approximately 23:00. When a Japanese soldier failed to return to his post, his company commander, Major Kiyonao Ichiki, thought that the Chinese had captured him, and reported the incident to his regimental commander, Colonel Renya Mutaguchi. Chinese regimental commander Ji Xingwen (219th Regiment, 37th Division, 29th Route Army) received a telephone message from the Japanese demanding permission to enter Wanping to search for the missing soldier.

At 23:40, General Qin Dechun, acting commander of the 29th Route Army and Chairman of the Hebei-Chahar Political Council was contacted by Japanese military intelligence with the same demand. He responded that in his opinion, the Japanese had violated China's sovereignty by conducting maneuvers without advanced notice, and refused the Japanese demand for entry into Wanping. However, Qin said that he would order Chinese troops stationed at Wanping to conduct a search on their own behalf with an attached Japanese officer. The Japanese were satisfied with the reply, but while both sides prepared their investigators, a unit of Japanese infantry attempted to breach Wanping's defences and were repulsed. An ultimatum by the Japanese was issued two hours later. As a precautionary measure, Qin contacted 37th Divisional commander General Feng Zhian to place his troops on heightened alert.
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ON JULY 7, 1937 a clash occurred between Chinese and Japanese troops near Peiping in North China. When this clash was followed by indications of intensified military activity on the part of Japan, Secretary of State Hull urged upon the Japanese Government a policy of self-restraint. In a conversation of July 12 with Japanese Ambassador Saito, Secretary Hull elaborated upon the futility of war and its awful consequences, emphasizing the great injury to the victor as well as to the vanquished in case of war. He said that a first-class power like Japan not only could afford to exercise general self-restraint but that in the long run it was far better that this should characterize the attitude and policy of the Japanese Government; that he had been looking forward to an early period when Japan and the United States would have opportunity for world leadership with a constructive program like that proclaimed by the American republics at Buenos Aires in December 1936 for the purpose of restoring and preserving stable conditions of business and of peace.