International legal positivists emphasized treaties as international agreements grounded in the state’s authority to establish and to enforce law based on its capacity as a sovereign power. The unfair treaties that Japan signed between 1858 and 1869 offered Japan the opportunity to develop an expertise in treaty law—especially in order to maintain its territorial integrity and to assert sovereignty over its territory. As the Japanese government successfully argued in the 1870s, Japan may have granted judicial jurisdiction to foreign consuls, but it retained legislative jurisdiction, and foreigners in Japanese territory were bound to obey the laws of Japan. An analysis of the foreign residents’ claims to rights to travel and to hunt in Japan demonstrates that a command of international law was key to Japanese control of Japanese territory.