LAUSR

Abstract The Middle Horizon (600–1000 CE) in the Central Andes was a time of important changes due to the expansion of the Wari and Tiwanaku states. Many scholars have argued that these polities, the Wari in particular, had a major economic impact on local communities, including the disruption of regional exchange networks and the reorientation of long-distance trade to the benefit of state elites. Obsidian data are particularly well suited to test this idea since provenience studies can trace the origin of obsidian artifacts. This paper presents new obsidian data from four local sites in the Cusco region dating from the Late Formative to the Middle Horizon to document the organization of trade networks through time and evaluate Wari impact on the local economy. A portable X-Ray Fluorescence (pXRF) spectrometer was used to determine the provenience of obsidian items recovered in horizontal excavations. Results indicate strong continuity in obsidian exchange through time. Like other early states worldwide, the Wari polity appears to have had limited impact on regional trade.