Moving metals IV: Swords, metal sources and trade networks in Bronze Age Europe

European Bronze Age swords had high functional and symbolic value, and therefore they are an interesting case for approaching questions of provenance and trade in Bronze Age Europe. It is often assumed that there is a strong affinity between metal supplies and artefact type. However, this study demonstrates that metal supply and sword types are mostly unrelated. In this paper we present a comparative provenance study of 118 Bronze Age swords, which includes lead isotope and trace elemental data for swords from Scandinavia, Germany and Italy dated between 1600 and 1100 BCE. About 70% of the swords have been analysed and published before while about 30% have been sampled and analysed for this study. The chronology and geography of the deposited swords indicate that the different regions relied on different metal trade routes which changed during the course of the Bronze Age. The analytical data indicates that the largest variation of the origin of copper is in the period of 1600–1500 BCE, when copper ores from Wales, Austria and Slovakia constituted the major copper sources for the swords. There is a visible change around 1500 BCE, when copper mines in the Italian Alps become the main suppliers for Scandinavian and Italian swords, while swords from Germany were foremost based on copper from Slovakia and Austria. Further, in the period 1300–1100 BCE the sources in the Italian Alps became the dominant supplier of copper for the swords in all regions discussed here.