A series of coercive acts, insults, and provocations by Western imperialist countries from the 1850s to the 1930s caused great anger to fester among the Japanese people. Japan's signing of unequal treaties with America, France, Holland, and Russia in 1858 placed restrictions on Japan's national sovereignty, such as extraterritoriality, which meant that foreigners in Japan had immunity from the jurisdiction of the Japanese legal system.