Radiocarbon dating and Hallstatt chronology: a Bayesian chronological model for the burial sequence at Dietfurt an der Altmühl ‘Tennisplatz’, Bavaria, Germany

This study is first attempt to refine Early Iron Age absolute chronology, specifically the timing of the Hallstatt C-D transition in southern Germany, using Bayesian chronological modelling of radiocarbon ( 14 C) dates. The Hallstatt period (c.800–450 BC) marks the transition from prehistory to proto-history in Central Europe. The relative chronological framework for Hallstatt burials developed by the mid-twentieth century is still used today, but absolute dating is limited by the scarcity of dendrochronological dates and the perception that 14 C dating in the Hallstatt period (HaC-HaD) is futile, due to the calibration plateau between c.750 and 400 cal BC. We present new AMS 14 C dates on 16 HaC-HaD burials from a stratified sequence at Dietfurt an der Altmühl ‘Tennisplatz’ (Bavaria, Germany). This sequence is situated entirely on the ‘Hallstatt plateau’, but by combining 14 C dating with osteological, stratigraphic, and typological information, we demonstrate that the plateau is no longer the ‘catastrophe’ for archaeological chronology once envisaged. Taking into account dendrochronological dating elsewhere, we show that at Dietfurt, the HaC-HaD transition almost certainly occurred before 650 cal BC, and most likely between 685 and 655 cal BC (68.3% probability), several decades earlier than usually assumed. We confirm the accuracy and robustness of this estimate by sensitivity testing. We suggest that it is now possible, and essential, to exploit the increased precision offered by AMS measurement and the IntCal20 14 C calibration curve to re-evaluate absolute chronologies in Early Iron Age Europe and equivalent periods in other regions.