Landscapes of State Formation: Geospatial Analysis of Aksumite Settlement Patterns (Ethiopia)

Abstract

Landscape-scale dynamics of the Kingdom of Aksum and its territories are exceptionally well-suited to help refine understanding of ancient complex polities in Africa and beyond. Archaeological explanations of ancient state formation have long centered on a small number of so-called primary cases that are thought to have inspired the rise of descendant, secondary states. Yet the rise of Aksum shows both local and multiregional influences which contradict diffusion and independent-origination focused explanations. Over four summer field-seasons (2005–2008), the Eastern Tigrai Archaeological Project (ETAP) targeted a 196-km2 inland area between Aksum and the Red Sea recording 137 sites, including 7 ancient towns larger than 6 ha. We report results of spatial analysis of site sizes, site clustering, trade routes, and spatial associations of sites with landforms and hydrology. Least-cost path GIS analysis of trade routes from Adulis to Aksum is broadly consistent with the reports of the Periplus Maris Erythraei, yet many travelers may have opted for a more circuitous highland itinerary rather than a direct least-cost route. Rank-size analysis reveals no conclusive evidence of site-size hierarchies suggesting, at least in this area, complex polities may not be characterized by clear categories of different size settlements. Ripley’s K multiscalar cluster analysis shows a spatial distribution of sites lacking pronounced clustering/dispersion, indicating that settlement locations were not determined predominantly by the proximity of neighbors. Finally, satellite imagery modeling shows statistically significant associations between settlements, landforms, and water-rich areas most amenable to high-productivity agriculture, showing environmental conditions played a pivotal role in shaping landscape-scale site patterning.