Abstract Recent work has argued that zoning is responsible for racial segregation, disparities in public goods provision, growing regional inequality, and exploding housing costs in productive areas. However, the slow-moving nature of land regulation’s effects suggests a crucial need for historical perspective to understand how zoning has shaped cities over the long term. This essay places the introduction of zoning in the broader context of urban development in the early twentieth century, with a focus on how the demand for separation of racial groups influenced some of the earliest zoning ordinances in American cities. We also discuss the long-run impact of zoning on the development of cities and highlight the key gaps in our understanding of the role of urban and suburban zoning in fostering segregation within cities and across metropolitan areas. A key lesson from our work in this area is that racial dimensions are important when studying land use regulations, even when the policies in question are ostensibly race neutral.