Japan Invades Manchuria

In September 1931, officers of Japan's Kwantung Army seized key cities in Manchuria, the resource-rich northeastern region of China, and within months controlled the whole territory. The invasion was carried out largely on the initiative of field officers rather than by government order, and it exposed the weakness of both civilian control in Japan and the League of Nations' ability to restrain a major power. Many historians regard it as the first step on the road to the wider Second World War in Asia.

Japan had held special interests in Manchuria since its victory in the Russo-Japanese War of 1904-05, when it took over Russian rights to the South Manchuria Railway and the leased territory at the tip of the Liaodong Peninsula. The Kwantung Army was stationed there to protect these holdings. By the late 1920s, Chinese nationalism was rising, and Chiang Kai-shek's government was extending its authority northward, which alarmed Japanese officers who saw Manchuria as vital for raw materials, markets, and defense against the Soviet Union. The Great Depression sharpened these anxieties and strengthened militarist voices at home.

The trigger came on the night of 18 September 1931, when a small explosion damaged a stretch of Japanese-controlled railway track near Mukden (now Shenyang). Japanese officers blamed Chinese saboteurs, but it is widely accepted that Kwantung Army conspirators staged the incident themselves. Using it as a pretext, the army attacked Chinese garrisons and quickly occupied major cities. The government in Tokyo initially tried to limit the fighting but could not rein in the army, and it ultimately accepted the results. Chinese forces in the region, whose commander Zhang Xueliang had been ordered to avoid escalation, offered little organized resistance.

In early 1932 Japan established the puppet state of Manchukuo, installing Puyi, the last Qing emperor, as its figurehead. China appealed to the League of Nations, which sent a commission headed by Lord Lytton. Its 1932 report found that Japan's actions could not be justified as self-defense and rejected recognition of Manchukuo, though it also acknowledged Japanese interests in the region. When the League adopted the report in February 1933, Japan walked out and soon announced its withdrawal from the organization.

The consequences were far-reaching. The League had shown it could condemn aggression but not stop it, a lesson noted by other expansionist states. In Japan, the army's success without punishment emboldened military factions and weakened party government, especially after political assassinations in the early 1930s. Manchuria became an industrial and strategic base for Japan, and tensions with China continued until full-scale war broke out in 1937.