# Uncovering a Medieval Pogrom: Genetic History of a Jewish Community in Catalonia (Spain)

## TL;DR

This study uses ancient DNA to uncover the genetic history of a Jewish community in medieval Catalonia, linking them to Jewish populations and confirming they were victims of a 1348 pogrom.

## Contribution

The first genomic analysis of medieval Iberian Jews, revealing their genetic affinities and confirming historical attribution to a pogrom.

## Key findings

- Genetic affinities with ancient and modern Jewish populations were identified through PCA and ADMIXTURE analyses.
- The Roquetes population's genetic composition is modeled as a mix of Canaan individuals and Iberian non-Jewish medieval people.
- Uniparental markers showed high diversity consistent with Jewish community patterns and background endogamy.

## Abstract

Background/Objectives. The Black Death pandemic, combined with the antisemitic climate of 14th-century Europe, led to widespread violence against Jewish communities, including numerous pogroms such as the one in 1348 in Tàrrega (Catalonia, Spain). In the Roquetes necropolis of Tàrrega, six communal graves containing at least sixty-nine individuals, with signs of violence, were dated to the mid-14th century. Based on the hypothesis that Iberian medieval Jewish communities preserve genetic similarities to other ancient and modern Jewish communities, our study aims to provide genomic information on medieval Iberian communities, which to date have been unknown. Methods. We analyzed DNA from sixteen individuals from the Roquetes necropolis using Twist ancient DNA enrichment capture. Several paleogenomic analyses based on nuclear DNA and uniparental markers were conducted to determine their genetic relatedness and population origin. Results. PCA and ADMIXTURE analyses revealed genetic affinities with ancient and modern Jewish populations. Uniparental markers, which exhibited high diversity, aligned with typical patterns within the Jewish community. The qpAdm modeling suggested that the genetic composition of the Roquetes population can be explained by a mixture of Canaan individuals (0.69) and the Iberian non-Jewish non-Islamic medieval population (0.31). No close genetic kinship was detected, but RHO analyses indicated a certain level of background endogamy. Conclusions. This is the first study to report genomic data for medieval Iberian Jews. Our findings reveal genomic affinities of the Roquetes individuals with ancient and modern Jewish populations and corroborate the previous attribution of the burials to victims of the 1348 Tàrrega pogrom.