Battle of Beiping – Tianjin The Battle of Beiping – Tianjin ( ) , also known as the " Peiking - Tientsin Operation " or by the Japanese as the ( 25 – 31 July 1937 ) was a series of battles of the Second Sino - Japanese War fought in the proximity of Beiping ( now Beijing ) and Tianjin . It resulted in a Japanese victory . Background . During the Marco Polo Bridge Incident on 8 July 1937 , the Japanese China Garrison Army attacked the walled city of Wanping ( 宛平鎮 ) after an ultimatum to allow its forces to search for an allegedly missing soldier had elapsed . Wanping , in the neighborhood of Lugou Bridge , was on the main railway line west of Beiping and was of considerable strategic importance . Prior to July 1937 , Japanese forces had repeatedly demanded the withdrawal of the Chinese forces stationed at this place . Chinese General Song Zheyuan ordered his forces to hold their positions and attempted to avert war through diplomacy . On 9 July , the Japanese offered a ceasefire and truce , one of the conditions of which was that the Chinese 37th Division , which had proven " hostile " to Japan , be replaced with another division from the Chinese 29th Route Army . This condition was agreed to by the Chinese the same day . However , from midnight of 9 July , Japanese violations of the ceasefire began to increase and Japanese reinforcements continued to arrive . Lieutenant General Kanichiro Tashiro commander of Japanese China Garrison Army fell ill and died on 12 July and was replaced by Lieutenant General Kiyoshi Katsuki . General Ma Bufang of the Ma clique notified the Chinese government that he was prepared to lead his army into battle against the Japanese when they started the attack on Beiping . Diplomatic maneuverings . Meanwhile , the Japanese civilian government of Prime Minister Konoe in Tokyo held an extraordinary cabinet meeting on 8 July , and resolved to attempt to defuse hostilities and settle the issue diplomatically . However , the Imperial Japanese Army General Staff authorized the deployment of an infantry division from the Chosen Army , two independent combined brigades from the Kwangtung Army and an air regiment as reinforcements . This deployment was rescinded on 11 July on news that negotiations were being held by the commander of the Japanese Northern China Area Army and the Chinese 29th Route Army on location , and with Japanese diplomats at the Chinese capital of Nanjing . However , even after General Song Zheyuan , Commander of the 29th Army and head of the Hebei - Chahar Political Council , was reported to have come to terms on 18 July , the Japanese Army pushed forward the deployment of reinforcements citing lack of sincerity on part of the Chinese central government . This mobilization was strongly opposed by General Kanji Ishihara on the grounds that an unnecessary escalation in the conflict with China was endangering Japan ' s position in Manchukuo vis - à - vis the Soviet Union . At Ishihara ' s urging , the deployment was delayed while Konoe used his personal contacts with Japanese acquaintances of Sun Yat - sen in an effort to establish a direct diplomatic settlement with the Kuomintang central government in Nanjing . This secret diplomacy failed when elements within the Japanese military detained Konoe ' s emissary on 23 July , and the mobilization of reinforcements was restarted on 29 July . One week later , the Commander of the Japanese Northern China Area Army reported that , having exhausted every means of peaceful settlement , he had decided to use force to " chastise " the Chinese 29th Route Army and requested approval from Tokyo . In the meantime , mobilization orders were issued for four more infantry divisions . The Langfang Incident . Despite the nominal truce , numerous violations of the cease - fire continued , including another shelling of Wanping by Japanese artillery on 14 July . By 25 July , Japanese reinforcements in the form of the IJA 20th Division arrived and fighting re - erupted first at Langfang , a city on the railroad between Beiping and Tianjin , between companies of Japanese and Chinese troops . A second clash occurred on 26 July , when a Japanese brigade attempted to force its way through Guanghuamen Gate in Beiping to " protect Japanese nationals " . The same day Japanese planes bombed Langfang . The Japanese then issued an ultimatum to General Song demanding the withdrawal of all Chinese forces from the outskirts of Beiping to the west of the Yongding River within 24 hours . Song refused , ordered his units to prepare for action , and requested large reinforcements from the central government , which were not provided . On 27 July , as the Japanese laid siege to Chinese forces in Tungchow , one Chinese battalion broke out and fell back to Nanyuan . Japanese planes also bombed Chinese forces outside Beiping and reconnoitered Kaifeng , Zhengzhou and Luoyang . On 28 July , the IJA 20th Division and three independent combined brigades launched an offensive against Beiping , backed by close air support . The main attack was against Nanyuan and a secondary attack against Beiyuan . Bitter fighting ensued with both General Tong Linge Deputy Commander of Chinese 29th Route Army and General Zhao Dengyu commanding Chinese 132nd Division being killed , and their units suffering heavy casualties . However , a brigade of Chinese 38th Division under General Liu Chen - san pushed back the Japanese in the Langfang area while a brigade of the Chinese 53rd Corps and a portion of the Chinese 37th Division recovered the railway station at Fengtai . However , this was only a temporary respite , and by nightfall General Song admitted that further combat was futile and withdrew the main force of Chinese 29th Route Army south of the Yungging River . Tianjin Mayor General Zhang Zizhong was left in Beiping to take charge of political affairs in Hebei and Chahar provinces with virtually no troops . General Liu Ruzhen ' s New Separate 29th Brigade was left in Beiping to maintain public order . The Tungchow Incident . On 29 July , the Japanese collaborationist East Hopei Army troops mutinied against the Japanese in Tungchow ( Tongzhou ) , killing most of their Japanese advisors and other civilians . Fall of Tianjin . Meanwhile on the coast at dawn of 29 July , the IJA 5th Division and Japanese naval forces separately attacked Tianjin and the port at Tanggu , which were defended by units of Chinese 38th Division and volunteers under acting commander Liu Wen - tien . General Huang Wei - kang ' s brigade defended the Taku Forts gallantly and also attacked a nearby Japanese airfield , destroying many aircraft . However , with increasing Japanese reinforcements his position was untenable , and that night ( 30 July ) General Zhang Zizhong was ordered to withdraw toward Machang and Yangliuching south of Tianjin , abandoning the city and Taku Forts to the Japanese . The fall of Beiping . On 28 July , Chiang Kai - shek ordered Song Zheyuan to retreat to Paoting in southern Hebei province . Over the next two days , intense fighting took place in Tianjin , where the Chinese forces put up a stiff resistance , but subsequently the Chinese retreated south along the lines of the Tientsin - Pukow Railway and the Peiping - Hankow Railway . On 4 August , General Liu Ruzhen ' s remaining forces withdrew into Chahar . Isolated , Beiping was captured by the Japanese without further resistance on 8 August 1937 . General Masakazu Kawabe entered the city on 18 August in a military parade , and posted proclamations at important points announcing that he was the new military governor of the city . Zhang was allowed to retain his position as mayor , but left the city secretly a week later . Aftermath . With the fall of Beiping and Tianjin , the North China Plain was helpless against the Japanese divisions which occupied it by the end of the year . The Chinese National Revolutionary Army was in constant retreat until the hard fought Battle of Taierzhuang . Zhang was vilified relentlessly by the Chinese press , and reviled as a traitor . Upon arrival at Nanjing he apologized publicly . Since he later died fighting against the Japanese , the Kuomintang posthumously pardoned Zhang for the events in Beiping .