Japan’s Unofficial War with China

by Sophie Hammond

During the early twentieth century, the Imperial Japanese Army invaded and occupied Chinese lands without ever officially declaring war.
In 1915, Japan issued the secret Twenty-One Demands to Chinese president Yuan Shikai, with the intent to claim economic and political power over China. The Demands were divided into five groups, with the Group Five demands including concessions similar to those Japan had forced on Korea. After twenty-five rounds of negotiations and intense political maneuvering on President Yuan’s part, the Twenty-One Demands were agreed to, except for the Group Five demands. The other Demands, though, reinforced Japanese control of southern Manchuria, Shandong, and eastern inner Mongolia. Japan’s hold on Manchuria was especially strong. The Chinese warlord Zhang Zuolin tolerated Japan’s encroachments on his Manchurian territory in exchange for their help maintaining his power, and Japan controlled southern Manchuria economically through its ownership of most of Manchuria’s railway lines and its lease of the Liaodong Peninsula.
In 1928, a handful of extremist Japanese officers stationed in Manchuria bombed Zhang Zuolin’s personal train, assassinating him. According to many sources, they acted without any direct orders from Tokyo, hoping to provide Japan with an excuse to invade Manchuria. Whether or not the Imperial Japanese Army actually authorized the assassination, Zhang Zuolin’s son and heir Zhang Xueliang was understandably not eager to ally himself with the Japanese after this. Instead, he gave his loyalty to the Nationalists, led by Chiang Kai-shek, who took as their main goal resistance to foreign influence in China.
The Manchurian railways also became a source of major contention, and to circumvent Japanese power in the region, the Chinese began building their own railway system which bypassed Japanese lines. It was these railways which formed the pretext for the Mukden Incident. Increasing tensions in the summer of 1931 culminated in the explosion of a bomb which destroyed a section of Japan-owned railway tracks near the city of Mukden. Japan blamed the Nationalists for the bomb, although even the League of Nations, after a thorough investigation, believed that the bomb had actually been planted by mid-level Imperial Japanese Army officers to justify seizing Manchuria.
The Mukden Incident, whether or not it was a staged pretext, is considered the beginning of Japan’s full-scale invasion of Manchuria and the beginning of Japan’s Fifteen Years’ War. By the next year, Japan had made Manchuria into Manchukuo, a puppet state headed by a puppet leader, the deposed Qing emperor Pu Yi. Pu Yi had become emperor of China in 1908 at the age of two, only for China to become a republic three years later. He lived in powerless luxury until 1924, when political turmoil in China caused him to appeal to Japan for protection. Eight years later, Japan made him Emperor of Manchukuo, and he lived again in powerless luxury.
As Japan pushed further and further into China and tightened its control over the regions it occupied, Chinese communist and Nationalist forces continued to fight against each other. However, in 1936, Zhang Xueliang, the leader of the Nationalists in Manchuria under Chiang Kai-shek’s command, forced Chiang to stop the civil war and ally with the communists to oppose the Japanese. Zhang achieved this unexpected result by kidnapping Chiang in Xi’an after Chiang arrived to order Zhang to resume fighting the communists. Chiang agreed to Zhang’s demands after communist leader Zhou Enlai intervened in the negotiations and helped persuade Chiang to fight more actively against the Japanese and to allow the communists local authority.
The Xi’an Incident of 1936 helped speed China on its way to a full-scale resistance to Japanese expansion, but most historians point to an incident at the Marco Polo Bridge near Beijing as the real beginning of the United Front against the Japanese. On the night of July 7, 1937, a small Japanese force demanded to be allowed into the walled town of Wanping to find a missing Japanese soldier. The Chinese garrison refused, and during the argument, a shot rang out. It remains a mystery which side fired the first shot, but soon enough, both sides began firing.
The clash at the Marco Polo Bridge bolstered Chinese resistance. Immediately, nearly all of the regional political and military groups in China threw their weight behind the Nationalists, even those who had formerly withheld their support. In September of that year, the Communists agreed to put their troops under Nationalist governmental control. This quickly escalated the fighting between Chinese and Japanese troops, as the Japanese seized several major Chinese cities and ports, including Shanghai in a three-month siege, followed by the unrestrained assault on the Nationalist capital, Nanjing, in what has become known as the Rape of Nanking. The Rape of Nanking further intensified Chinese resistance, and while the Imperial Japanese Army continued to expand their control over parts of China, their progress was stymied outside urban areas.
Yet war remained officially undeclared by either side until December 9, 1941, when the United States and China simultaneously declared war on Japan after the attack on Pearl Harbor.

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