This article examines the tensions surrounding the opening of Seoul to foreign trade and residence and how mixed residence and extraterritoriality played a decisive role in the boundaries of residence in Seoul as well as the boundaries of jurisdiction and citizenship in Korea from 1876 to 1910. Different from most capital cities in East Asia, Seoul opened in 1882 as a city of mixed residence with no foreign settlements established exclusively for foreign residents. As a result, the entire space inside the walls became an arena where multiple extraterritorialities directly challenged the sovereignty of the Korean state. It was against this backdrop of imperial powers’ growing presences and their attempts to make Seoul into an extraterritorial space that the newly established Taehan Empire strove to refashion Seoul into the imperial capital Hwangsŏng, as a means to reinsert its power into the capital’s space and residents. Despite its efforts, however, this article shows that the Korean government was losing its grip on both the capital’s space and residents, as a growing number of opportunistic Koreans evaded Korean jurisdiction by taking advantage of extraterritoriality or obtaining foreign citizenship.