China's Nanjing Decade
East Asia 1931.0918
The Northern Expedition, early Chinese Civil War, and Japanese incursions into China (18 September 1931)
Historical Map of East Asia & the Western Pacific
With the help of the Fengtian clique, Chiang Kaishek won the Central Plains War and was able to turn his attention to the reemergence of the Chinese Communist Party in the south. However Japanese militarists viewed Chiang's growing power with concern and, when a suspicious explosion occurred on the Japanese owned South Manchuria Railway near the Chinese city of Mukden, they were ready to act.
Treaty ports were towns opened to foreign trade by unequal treaties in China. Foreigners operating within treaty ports enjoyed extraterritoriality, being subject to their home country's laws. Unlike concessions such as Hong Kong, these territories were not directly leased by the foreign powers and did not have sizable foreign garrisons.
Treaty ports are not shown in the maps after the 1911 Chinese Revolution in order to give a clearer picture of the chaos in China itself and as by that point their numbers had stabilized. After the revolution, some of the smaller ports were phased out while the others became less important as the situation in China meant that only the concessions could provide foreigners with security. Most, however, still continued on into the 1940s when the Japanese entry into World War II and foreign agreements with China brought them to an end.
See this map for treaty ports in 1907, when the system was at its peak.
By the terms of the Treaty of Tientsin (1858), foreign vessels including warships had the right to free navigation on the Yangtze River. In practical terms, this right extended only as far as Yichang until 1900, when advances in steam navigation allowed access as far inland as Chongqing.
Nationalist victory in Central Plains War
Chiang Kaishek's Nationalist regime defeats rivals in Central Plains War
Fengtian clique takes Beiping in support of Chiang Kaishek's Nationalist regime
Britain returns Weihaiwei to China
Chinese Nationalists begin their Encirclement Campaigns against the Communists
Chen Jitang, governor of Guangdong, rebels across authority of Chinese Nationalist regime
First Ma intervention in Xinjiang
Ma Zhongying, a Muslim warlord of Gansu province and a member of the Ma clique, invades Xinjiang province to support the Kumul Rebellion in western China. Ma claims his intervention is on behalf of the National Government of China - which has indeed secretly agreed to recognize him if he captures Xinjiang from the reigning governor Jin Shuren. However, he fails to capture the city of Kumul and is forced to withdraw after he is wounded.
Japanese Army uses a staged terrorist attack on the South Manchuria Railway as an excuse to invade Manchuria