The use of Historical Geographical Information Systems (HGIS) technology has been increasing in recent years. Maps used in GIS systems must be geo-referenced—that is, common coordinates or other information must be embedded in images so that multiple datasets can be applied to the same space. The technology has been in use for many years among geographers, but has only recently come to the attention of historians. At the same time, software programs for creating and viewing geo-referenced materials have become more widespread. A number of websites are now available that illustrate some of the possibilities in relation to economic history topics:
A short bibliography geared to explaining GIS to historians:
Beyond Steel: An Archive of Lehigh Valley Industry and Culture
Urban Transition Historical GIS Project
Mapping Decline: St. Louis and the Fate of the American City
David Rumsay Map Collection GIS Examples
Mapping the Du Bois Philadelphia Negro
Digital Harlem: Everyday Life, 1915-1930
The Grub Street Project: Topographies of Eighteenth-Century London
Shaping the West (Richard White on Railroads)
A Vision of Britain through Time
National (US) Historical GIS and Social Explorer
A short bibliography geared to explaining GIS to historians:
Anne Kelly Knowles, Past Time, Past Place: GIS for History, and Placing HistoryUpdate, July 29, 2011: See also Patricia Cohen's article in the July 26 New York Times, "Digital Maps Are Giving Scholars the Historical Lay of the Land."
David J. Bodenhamer, et al., The Spatial Humanities
Ian Gregory and Paul Ells, Historical GIS