What explains the abolition of extraterritoriality in world politics? Which factors account for the variation in the timing of the abolition process? I develop a state-building explanation for the abolition of extraterritoriality. I find that traditional explanations of the abolition of extraterritoriality that rely on power and culture do not account for Western states’ decisions to keep or abolish extraterritoriality. I suggest that the state-building practices of non-Western countries, specifically the institutionalization of a state-based legal system, are key to explain­ing why Western states decided to keep or abolish extraterritoriality. I test my argument against alternative explanations using a comparative case study of the abolition process in Japan and China.

 The Extension of Westphalian Sovereignty