National Historical Geographic Information System

National Historical Geographic Information System
Name	National Historical Geographic Information System
Abbreviation	NHGIS
Established	2011
Type	Research infrastructure
Location	Minneapolis, Minnesota
Coordinates	44.9778°N 93.2650°W
Parent organization	Minnesota Population Center

National Historical Geographic Information System is a digital research infrastructure that aggregates historical census data and cartographic boundary files for the United States into a unified spatial database. It supports quantitative historical inquiry by integrating decennial census counts, cartographic shapefiles, and metadata to enable temporal and spatial analysis across counties, states, and census tracts. NHGIS underpins scholarship linking historical demography, urbanization, migration studies, and public policy history with geospatial methods.

Overview

NHGIS was developed at the Minnesota Population Center within the University of Minnesota and builds on collaborations with institutions such as the National Archives and Records Administration, the United States Census Bureau, the Library of Congress, the Inter-university Consortium for Political and Social Research, and the Social Science Research Council. It supplies aggregate data derived from decennial censuses from the early 19th century through recent censuses, paired with historical cartographic boundaries curated from sources like the U.S. Geological Survey, the Sanborn Fire Insurance Maps, and state archives in Massachusetts, New York (state), Pennsylvania, Ohio, and Illinois. The project advances methods used in studies by scholars affiliated with the American Historical Association, the Economic History Association, and the Journal of American History.

Data and Methodology

NHGIS compiles harmonized tables of population counts, housing characteristics, occupational classifications, and other variables drawn from decennial censuses conducted by the United States Census Bureau and microdata samples from projects like the Integrated Public Use Microdata Series. Spatial joins between tabular data and cartographic boundaries rely on georeferencing methods developed with tools such as ArcGIS, QGIS, and programming libraries from Esri and the R Project for Statistical Computing. Metadata standards reference the Dublin Core and practices promoted by the Digital Public Library of America and the Open Geospatial Consortium. Digitization efforts have incorporated resources from the National Historical Publications and Records Commission, the HathiTrust Digital Library, and university presses including Oxford University Press and Cambridge University Press that publish methodological guides.

Major Projects and Datasets

Key NHGIS products include harmonized Decennial Census tables, time-series crosswalks for boundaries, and historical cartographic shapefiles for counties, places, and minor civil divisions. Major datasets draw on the 1790 United States Census, the 1860 United States Census, the 1870 United States Census, the 1880 United States Census, the 1890 United States Census reconstruction efforts, and 20th-century censuses including the 1940 United States Census and the 1950 United States Census. Spatial datasets incorporate the Public Land Survey System, county boundary changes recorded by state historical societies, and geospatial products used in projects like the HGIS de las Indias and comparative work linked to the European Historical GIS community. NHGIS has partnered with initiatives such as the American Community Survey integrations and mapping efforts tied to the National Historical GIS Project at universities and the Center for Spatial and Textual Analysis.

Applications and Uses

Researchers use NHGIS for studies in historical urbanization exemplified by analyses of New York City, Chicago, Boston, and Philadelphia; labor market transformations studied in regions like Detroit and Pittsburgh; migration and settlement examined through cases in St. Louis, Minneapolis, and New Orleans; and electoral geography work linking historical vote returns for the United States House of Representatives, the United States Senate, and presidential elections. Public historians and museums such as the Smithsonian Institution and the New-York Historical Society employ NHGIS data for exhibits, while planners and non-profits including the Brookings Institution and the Urban Institute use datasets for comparative historical policy analysis. Pedagogy in programs at the Harvard University, Yale University, Columbia University, Princeton University, and the University of California, Berkeley integrates NHGIS into coursework on urban history, demography, and geographic information science.

Governance and Funding

NHGIS is governed by staff at the Minnesota Population Center with advisory contributions from scholars affiliated with institutions like the National Science Foundation, the Andrew W. Mellon Foundation, and the Russell Sage Foundation. Funding has come from grants awarded by agencies and organizations including the National Institutes of Health, the Institute of Museum and Library Services, the Alfred P. Sloan Foundation, and the National Endowment for the Humanities. Collaborations involve partnerships with the Library of Congress, the New England Historic Genealogical Society, state archives from Virginia, North Carolina, Georgia, and Texas, and consortia such as the Digital Humanities Start-Up Grants and the Council on Library and Information Resources.

Criticism and Limitations

Critics note limitations in NHGIS related to the uneven historical coverage of minority populations documented in censuses such as the 1790 United States Census and the 1880 United States Census, measurement changes following legislation like the Civil Rights Act of 1964 and shifts in census questions over time. Some historians point to challenges with imputing data across boundary changes exemplified by complex redistricting histories in states like California and Florida, and to errors arising from digitization of sources like the 1890 United States Census fragments lost in the 1890 United States Census fire. Methodological debates engage communities working on the Trans-Atlantic Slave Trade database, reparations research concerning the Civil War, and reconciliation work with Native nations including the Cherokee Nation and the Navajo Nation over historic place naming and territorial mapping. Additional concerns arise about long-term sustainability debated at forums hosted by the American Antiquarian Society and the Council on Library and Information Resources.

Category:Historical GIS