The origin and legacy of the Etruscans through a 2000-year archeogenomic time transect

Abstract

The origin, development, and legacy of the enigmatic Etruscan civilization from the central region of the Italian peninsula known as Etruria have been debated for centuries. Here we report a genomic time transect of 82 individuals spanning almost two millennia (800 BCE to 1000 CE) across Etruria and southern Italy. During the Iron Age, we detect a component of Indo-European–associated steppe ancestry and the lack of recent Anatolian-related admixture among the putative non–Indo-European–speaking Etruscans. Despite comprising diverse individuals of central European, northern African, and Near Eastern ancestry, the local gene pool is largely maintained across the first millennium BCE. This drastically changes during the Roman Imperial period where we report an abrupt population-wide shift to ~50% admixture with eastern Mediterranean ancestry. Last, we identify northern European components appearing in central Italy during the Early Middle Ages, which thus formed the genetic landscape of present-day Italian populations.

Fig. 1.. Geographic and temporal distribution of the newly produced dataset.

(A) Geographic map of the Italian peninsula (right) including a zoom-in (left) indicating the maximum extension of Etruscan territories and the location and number of individuals for each archeological site newly analyzed here (not filled symbols refer to individuals with no certain date). (B) Mean radiocarbon dates and 2-sigma intervals for each dated individual or samples genetically related to those individuals (four radiocarbon dates for S.Italy_Venosa are grouped, reporting their lowest and highest 2-sigma values) (table S1, A and B).

Fig. 2.. Genetic map and clustering of ancient and present-day populations.

(A) PCA inferred from genomic variation of 60 West Eurasian populations genotyped on the Human Origins array (gray dots with geographic regions labeled in gray) including present-day Italians (circles without outline) onto which we projected the newly reported ancient individuals (symbols with outline, not filled for nonradiocarbon-dated individuals) and comparative ancient populations (stars without outline). (B) Unsupervised admixture (K = 11) of comparative ancient individuals and 20 present-day central Italians (TSI.SG). (C) Unsupervised admixture (K = 11) of newly reported ancient individuals excluding genetically related individuals. WHG and CHG refer to Western and Caucasus hunter-gatherers, while SW and NE Europe refer to southwestern and northeastern Europe, respectively.

Fig. 3.. Genetic placement and modeling of Iron Age and Roman Republic individuals.

(A) PCA of Italian individuals from the Iron Age and Roman Republic (symbols with outline) plus Copper and Bronze Age individuals from Italy and other source populations (symbols without outline) used in qpAdm. Gray dots represent present-day West Eurasian individuals (see Fig. 2A). (B) Proportion of steppe-related ancestry in C.Italy_Etruscan and C.Italy_Etruscan.Ceu as estimated with qpAdm (table S4B). MN and EBA refer to Middle Neolithic and Early Bronze Age, respectively.

Fig. 4.. Genetic placement and modeling of Iron Age and Imperial period individuals.

(A) PCA of Italian individuals from the Iron Age to the Imperial period (symbols with outline) plus Bronze and Iron Age individuals (symbols without outline) used as source populations in qpAdm. Gray dots represent present-day west Eurasian individuals (see Fig. 2A). (B) Proportion of C.Italy_Etruscan ancestry in Iron Age outlier groups and in C.Italy_Imperial as estimated with qpAdm. For each test, the reported non-C.Italy_Etruscan population is the one providing a proportion that is closest to the median among all fitting models (table S4D). MBA, MLBA and LBA refer to Middle, Middle-Late and Late Bronze Age, respectively, and IA refers to Iron Age.

Fig. 5.. Genetic placement and modeling of Early Middle Age and present-day individuals.

(A) PCA of Italian individuals from the Imperial to the Early Medieval periods (symbols with outline) and present-day Italians (symbols without outline). Gray dots represent present-day west Eurasian individuals (see Fig. 2A). (B) Proportion of northern ancestry from Longobard-related individuals in C.Italy_Early.Medieval as estimated with qpAdm (table S4E). (C) Proportion of C.Italy_Early.Medieval and S.Italy_Venosa ancestry in modern-day central Italians (Tuscan.DG) and southern Italians, respectively, as estimated with qpAdm (table S4G).