A finer resolution for historical residential segregation: Geocoding and analyzing the population of 1860 Washington, D.C.

Abstract

This study geolocates the place of residence for a majority of free residents in Washington, D.C. in the year 1860 using archival data and evaluates their spatial distribution with respect to racialized residential segregation patterns. Transcribed individual census entries were joined to city directory records and geocoded at the household level using a customized historical address locator derived from period street directories in order to extract socioeconomic details at a fine scale. These data points are used here to contextualize early segregation patterns in Washington, and additionally they were joined to city blocks to conduct quantitative analyses of racialized residential segregation. Measurements at the city block level indicate a moderately high degree of unevenness and isolation between the White and Black population already present in the years before the 1861–1865 US Civil War (antebellum) Washington, well ahead of the widespread development of alley style housing that drove microscale racial segregation in subsequent decades.