The DNA history of Spanish and Portuguese people is deeply intertwined with the diverse populations that have settled in the Iberian Peninsula over millennia. Genetic studies on the Iberian population reveal a complex mosaic of ancestries, reflecting the peninsula's role as a crossroads between Europe, North Africa, and the Mediterranean. From ancient hunter-gatherers to the spread of Neolithic farmers, and later migrations, the genetic landscape of Iberia has been shaped by a series of significant demographic events.

One key element in the genetic makeup of modern Iberians is the Bell Beaker ancestry in Iberia. The Bell Beaker culture, which spread across much of Europe during the late Neolithic and early Bronze Age, left a significant genetic imprint on the Iberian population. This culture is associated with a migration of people from Central Europe into the Iberian Peninsula, contributing to the genetic diversity observed in contemporary Spanish and Portuguese populations. Additionally, the arrival of Arab and Berber peoples during the Islamic expansion into the Iberian Peninsula introduced Arab ancestry in North Africa and the Mediterranean into the gene pool. This period, marked by centuries of Muslim rule in parts of Spain and Portugal, added another layer to the rich genetic heritage of the region. These various ancestries, combined with the influence of later migrations and interactions, have created a uniquely diverse genetic profile that continues to define the people of the Iberian Peninsula today.