The Mukden Incident of 1931 - commemorated in China every year as an act of Japanese aggression - saw Japanese troops blow up a railway in northeastern China as an excuse to take over Manchuria. Japan had already been expanding its territory in Asia militarily for several decades. After defeating China in 1894-95, it established itself in the Korean Peninsula, Taiwan and southern Manchuria, and by winning a 1904-05 war with Russia it solidified control of Korea, which it later formally colonised. Tokyo had a particular interest in resource-rich Manchuria, a strategic location and an industrial and transport hub - benefits that seemed vital given the global economic troubles experienced at that time. Japanese officials in Manchuria also felt growing pressure to assert control of the area, to thwart rising popular dissatisfaction with their presence and increasing closeness with China "proper" south of the Great Wall. The ethnic Han Chinese population had grown in recent decades through immigration to the region, home to the indigenous Manchus. Meanwhile, Chinese Nationalist leader Chiang Kai-shek had unified China, and in 1928 Manchurian warlord Zhang Xueliang pledged loyalty to him. Japanese officers in Mukden - today the city of Shenyang in Liaoning province - took matters into their own hands, despite hesitation in Tokyo. They blew up part of the Southern Manchurian railway, blamed the incident on Chinese dissidents and used it as a pretext to take control across the region. By 1932 they had taken over Manchuria and turned it into the puppet state of Manchukuo, nominally headed by the Chinese emperor Pu Yi. The region remained isolated from the rest of China until Japan was defeated in 1945. Source: Modern China, a Reader by Graham Hutchings
