Mapping Power: Using HGIS and Linked Open Data to Study Ancient Greek Garrison Communities

From controlling cities within the Athenian Empire in the fifth-century BCE to maintaining isolated outposts on the border of the Parthian Empire in the second-century CE, the institution of the phrourarchia was a critical component of Greek civic and military identity. Despite its longevity and importance to the Greek world, the office has long been overlooked in scholarship, which has largely viewed the office as an isolated regional phenomenon without distinguishing between its local and imperial manifestations. There has also has been no definitive catalog of the institution or its commanders, or any attempt to show the full spatial extent of the institution in the Greek world. Until recent developments in digital gazetteers and Linked Open Data (LOD), identifying and mapping all of the phrourarchia in the Greek world was a nearly insurmountable task. However, the advent of the Pleiades project and the Linked Ancient World Data initiative has made such a project feasible. This article illustrates how new advances in HGIS and semantic web technologies has created a robust and expanding academic community and the development of best practices around the concept of sharing geospatial humanities data. After discussing the development of the ancient world LOD ecosystem, this article addresses how these resources were used to identify, locate, and study all of the garrison communities and commanders comprised the institution of the phrourarchia until the second-century CE. I discuss the creation of the first map to show all the phrourarchia, and how that task reveals that, although the institution was spread across the Greek world, the specific office of the phrourarchos, (plural phrourarchoi), or garrison commander, was primarily located in Egypt and south east Asia Minor. Mostly known through inscriptions, the presence of phrourarchoi signaled a complex interaction between imperial powers and local communities that later Greek and Roman historians often minimized or ignored. Phrourarchoi deployed by imperial powers were mostly found in subjugated communities and at the periphery of empire, and were almost unknown in imperial capitals. In contrast, phrourarchoi employed by smaller communities could be located anywhere from watchtowers at the edge of a city’s territory to fortresses within the very heart of the community. I argue that the varying locations of garrisons and commanders, in addition to the different regulations that governed the office, reveals that imperial phrourarchoi were highly specialized individuals who supported the imperial administration of their employers through a blend of intentionally vague civic and military responsibilities. In contrast, smaller communities used phrourarchoi who were largely amateurs, and had clear limits on their purely military authority. Following my analysis of the phrourarchia and how GIS methodologies aided my investigation, I close the article with a discussion of some of the shortfalls of current GIS approaches (A preliminary digital project based on this investigation is available here: http://awmc.unc.edu/awmc/applications/snagg/) .