Asia Pacific 1915: Japan's Twenty-One Demands
Early in World War I, Japan seized the German Kiautschou Bay concession in eastern China. The next year they presented a set of 21 demands to the Chinese government to accept expanded Japanese influence in China. In the end President Yuan Shikai agreed to 13 of the demands, but Japan's actions had created resentment in China and suspicion in Britain and the United States.
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.
14 Oct 1914 Japan occupies Mariana Is.▲
Japanese forces occupied Saipan, the administrative center of the German-ruled northern Mariana Islands.
31 Oct–7 Nov 1914 Siege of Tsingtao▲
23,000 Japanese infantry, joined by Japanese naval forces and a symbolic contingent of 1,500 British troops from Tianjin, surrounded Tsingtao (now Qingdao), the main port and center of the German-leased Kiautschou Bay concession in eastern China. The town was defended by 3,650 German troops, several hundred Austro-Hungarians, and a few warships. After a week-long siege - in which the Japanese conducted the world's first naval-launched air raids from the seaplane carrier Wakamiya - the Germans agreed to surrender.
18 Jan 1915 Japan's Twenty-One Demands▲
Japan presented its Twenty-One Demands to Yuan Shikai, President of China, threatening dire consequences if they were rejected. The Demands were to confirm Japanese seizure of German ports and infrastructure in China, extend Japan's leasehold over the South Manchuria Railway Zone, give Japan control over central Chinese mining, bar China from making further concessions to other foreign powers, and accept Japanese advisers. After initial rejection, China would accept a reduced set of 13 demands on May 25.