A mere four decades after the First Sino-Japanese war (and after six years of fighting on and off), the Japanese launched an all-on assault against the Chinese on July 7, 1937 at Marco Polo Bridge. Superior in every way to their counterparts on the mainland, the Imperial Japanese Army (IJA) soon controlled Beiping and Tianjin, opening up what would become the Pacific Theater in World War II.
The Marco Polo Bridge had tremendous strategic value. Sitting on the Yongding River less than ten miles from Beijing, the structure was once praised by the Venetian traveler when he laid eyes on the original structure – one completed in the late 1100s. In early June, the IJA began a series of heavy maneuvers in the area every night. Uncomfortable with the movements yet willing to allow them, the Chinese government requested advance notice for the sake of nearby residents, hoping to keep them from being too worried by the sound outside. The Japanese, for their part, agreed to this compromise.
Despite these precautions, everything went wrong on the night of July 7th. Chinese troops, startled by an unannounced action from their Japanese counterparts, began firing across the river in defense at about 11:00pm. Fire was briefly returned, then the incident seemed to have settled down just as quickly as it popped up – until an IJA soldier came up missing.
Major Kiyonao Ichiki feared the worst: his comrade had been captured by an advancing Chinese army. He contacted his commanding officer, who sent a message to his opposite number in the Chinese regiment across the bridge demanding the right to search for the soldier in Wanping. The IJA intelligence team reached out to the Chinese General in no uncertain terms: “Let us find our man or else.”
Stinging because the maneuvers had been carried out despite the lack of notice, the general flatly denied the strongly-worded request. Believing his country to be the victim, the commanding officer instead offered to conduct the search with a Japanese officer attached to the local Wanping group. The two sides agreed to the compromise, gathering the appropriate men to investigate the incident.
The two-hour window to organize the rescue mission turned out to be too long. A small group of IJA infantry lunged into Wanping in the hopes of piercing the Chinese defensive line – and were pushed back. Reacting to the loss, Japanese reinforcements slid into position behind their brothers in arms. The Chinese, assuming the mistaken unit had been merely the opening salvo, pushed a division in to offer more support to their regiment.
Just after 5:00am on July 8th, mere minutes since the two appointed Japanese investigators had arrived looking for the missing soldier, the IJA opened fire on Wanping. With machine gun bullets zipping through the tiny town, elements of the Japanese infantry made a move for the bridge, gaining ground and inflicting severe casualties.
The Chinese responded swiftly, soon backing the 100 men on duty with an additional regiment and sweeping through the rain on July 9th to retake the Marco Polo Bridge. The Japanese immediately contacted the government in Beijing, looking to agree a truce – offering an apology in exchange for the Chinese regiments moving out of the area. The Chinese obliged, but the conflict escalated: skirmishes and rhetoric became more severe.
Less than three weeks later, negotiations began again, but this time they would not take. On August 9th, the murder of a Japanese naval officer brought the tensions to a boil – one that would last eight years until surrender was signed on the USS Missouri in September 1945.