Abstract
Italian genetic history was profoundly shaped by the Romans. While the Iron Age Central Italian gene pool was comparable to that of other coeval Central/Western European regions, during the Imperial age, it was significantly influenced by Eastern Mediterranean ancestries. To explain this genetic shift, it has been proposed that people from eastern provinces of the Empire migrated toward its political center: Rome and its surroundings. In this study, by presenting a new Roman Republic individual (1.25×) and comparing it to other published Republican samples, we propose a novel perspective for the presence of the Eastern Mediterranean ancestry in the Imperial gene pool. We show that the spread of this genetic ancestry may have taken place earlier than previously thought, during the Late Republican period, therefore predating the onset of the Empire by ∼200 years. The diffusion of this ancestry occurred due to early East-to-West movements, either because Eastern Mediterranean regions were under Roman political influence since the Late Republican period or even as a result of internal movements from Southern Italy where several Greek and Phoenician settlements were established during the 1st millennium BCE.