The Romans left a profound mark on the Iberian Peninsula, visible in Latin, Roman law, aqueducts, bridges, amphitheaters, and triumphal arches. Thanks to genetics, we now know that their arrival also changed the population's DNA. A study led by researchers from the Autonomous University of Barcelona (UAB) and published in the journal iScience has obtained the most complete and accurate image to date of the history and genetic evolution of the Iberian peoples who inhabited the northeast of the Iberian Peninsula from the beginning of the Iron Age to the Roman conquest, between 2,700 and 2,100 years ago.