Introduction to Historical GIS and the Study of Urban History

Abstract

Over the past decade or so geographic information systems (GIS) methodology has become an accepted tool in historical research (Gregory and Ell 2007; Knowles 2008). Although often regarded as a mapping tool, GIS is perhaps better thought of as a type of database. What makes a GIS database unique is that a location is stored for each item of data, with this location taking any of a variety of forms: a point, a line, a polygon representing an area or zone, or, in the case of a raster system, a pixel. GIS can then present instantly on the screen a map showing the distribution of any variable or combination of variables in any of the chosen locational formats. This electronic display of information becomes an analytic tool, allowing the refinement of research questions, with answers displayed instantly: GIS creates a display of information once visible only in paper form, drawn slowly and expensively first by cartographers and then by vector plotters. GIS and its associated tools transform mapping into a dynamic exploratory process.