This project uses the international history of urban planning in the twentieth century to recast the growth of cities—London, New York, Tokyo—within the frame of environmental history. The development of the modern metropolis was, I contend, less a process of denaturing urban space than of renaturing the ecologies that defined everyday life in modernizing societies. Focused most closely on the rebuilding of Tokyo after the Great Kantō Earthquake of 1923 but multi-national and multi-archival in approach, The Nature of Cities uses the international history of urban modernism to illuminate the intellectual and material networks that crisscrossed national borders in the mid-twentieth century to redefine the relationship between urban populations and the natural environment around the world.