Population Density in Nineteenth-Century American Urbanism

Population density and size are the most commonly used metrics for defining modern cities and urbanism. Yet unlike size, density has been overlooked in systematic analyses of the historical development of the U.S. urban system. Deploying large-scale geocoded census microdata on forty major cities in 1880, this article contributes to a systematic understanding of density in late-nineteenth-century U.S. urbanism. Methodologically, we make the case for a block-level, population-weighted density measure that reflects the experience of density and is transferable to other urban contexts. Thematically, we use this measure to compare density across cities, outlining regionally distinct patterns in density and identifying the built environment as a contributing factor to high- versus low-density urban development, and to explore density within cities across population subgroups, finding that immigrants, racial minorities, and lower class residents experienced higher densities at a time when high density increased exposure to health risks. Additionally, throughout the article we draw out preliminary findings worthy of future research about density conditions for particular cities, places, and demographic subgroups.