Bridging the time gap in the Bronze Age of Southeast Asia and Southwest China

Bronze working is a nonnative technical craft which was incorporated relatively late in southern China and Southeast Asia. Debates about the origins of the Bronze Age in these regions hinge on finding the "missing" geographic linkages facilitating the cultural transfer of knowledge during the second millennium BCE. We provide the first series of AMS assays from Bronze Age sites in the Lake Dian basin in Yunnan and definitively connect the timing of tin-bronze metalworking in southwestern China with sites in Northeast Thailand to the 11th to 10th c. BC. Using Bayesian modeling to calibrate dates from stratified deposits, we propose a revised chronology for the Bronze Age and present a division spanning three phases (early, middle, and late). The findings indicate the establishment of settlements beginning in the early 12th c. BC, accompanied by the incorporation of copper-base metallurgy (1100/1000-800 BCE), a middle (800-600 BCE) and late 'Dian' period (600-250 BCE) that is identified with the emergence of a bronze drum culture. The revised chronology not only pushes back the timing of copper-base technology in central Yunnan by at least five centuries before the material medium was co-opted by elites as a means of wealth production. Temporal correspondences between the Dian sequence and other prehistoric complexes in the region also strengthen arguments for a potential technological link between Yunnan and Mainland Southeast Asia (MSEA) and the transfer of tin-bronze metallurgical knowledge across geographic regions.