Deceptive Contiguity: The Polygon in Spatial History

Abstract

The polygon is the most common vector data model used to represent political entities in spatial history and historical GIS. When it comes to visualizing the entangled, complex political geography of early modern societies, however, discrete, contiguous features can be a problematic cartographic choice. One example explored in detail here is the aggressive enserfment of foreign peasants by the Electoral Palatinate in the seventeenth-century Holy Roman Empire. The comparison of an older map of these events with GIS maps based on new data shows how the polygons on the older map exaggerate the extent of Palatine expansion and suggest a continuous distribution of phenomena that were really discontinuous. Indeed, in early modern political geography, the polygon often operates as the cartographic equivalent of problematic concepts such as absolutism and sovereignty. Though point-based maps offer more accurate representations of pre-modern spatial orders, they hinge on the availability of geospatial data. Discussing the potential and limitations of different kinds of spatial data available to early modern historians today, the conclusion calls for a more argument-driven spatial history of early modernity.