My dissertation investigates the impact of the opium trade and culture on urban institution-building and the production of `modernity` in the Manchurian city of Dairen throughout the period of Japanese control (1905-1945). In the early twentieth century, Dairen presented itself as a consummately modern, Japanese colonial capital. Yet the city also constituted the world’s second-largest opium shipping and distribution port, and its residents consumed the highest per-capita volume of opium recorded in history. I seek to deconstruct the ways in which official efforts to both stimulate demand for the drug and conceal its effects influenced municipal and regional politics, the built environment, labor and the legitimate economy, the juridical system, public health and urban culture. I examine Dairen in both the pre-Manchukuo and Manchukuo eras in order to illuminate, through the lens of opium policy, change and continuity in political ideology, the economy, demography and culture. Through this project, I hope to contribute to the growing field of‘Manshu studies,` to highlight the salience of the opium trade in Japanese empire-building, and to return agency to Japanese and Chinese actors in this‘transnational` region. In broader terms, I aspire to increase our understanding of the early twentieth-century city, and to further efforts to integrate the study of the Japanese empire into global history.