In a classic act of opportunism, the Japanese government used the distraction of the World War I in Europe to press China secretly for a series of concessions. It was made clear that if China were to refuse these demands, war with Japan would be the result.
The demands, originally 21 in number, included such matters as the following:
The Japanese would henceforth receive coal and iron mining rights in central China and the Shantung Peninsula
The Japanese would be granted extensive rights in a number of Chinese port cities
China would be required to end the practice of leasing land and facilities to other nations
Control over certain Chinese internal affairs, such as financial and police matters, would be assigned to Japanese agents.
The Chinese skillfully drew out the negotiations, but were eventually forced into agreeing to a revised set of demands in May 1915. Pressure from the United States and Britain was responsible for removing the most odious provisionthat of installing Japanese advisory agents.
China also managed to get in the last word by directing its legislature to refuse to ratify the agreements formally incorporating the demands; Japan chose to ignore this inaction.
The revised Twenty-One Demands enabled Japan to establish a position in China similar to that enjoyed by the other great powers. However, by threatening China with war, the Japanese provoked the Chinese people's continued hatred and the other Allies' growing suspicion.