A groundbreaking genetic study conducted by a team from Oxford University has reshaped our understanding of British ancestry. According to the research, the Celts—long believed to have descended from Central European tribes—are in fact the descendants of a tribe of Iberian fishermen who crossed the Bay of Biscay approximately 6,000 years ago.

Led by Professor Bryan Sykes, a renowned expert in human genetics at Oxford, the team discovered that the DNA of many people in the British Isles bears a near-identical genetic “fingerprint” to that of inhabitants of Spain’s northern coastal regions. These Spanish populations are themselves descendants of ancient migrants who journeyed north between 4,000 and 5,000 BCE.

“This is not just a tweak to British history—it’s a fundamental shift,” said Professor Sykes, who is preparing to publish the first comprehensive DNA map of the British Isles. “Around 6,000 years ago, Iberian peoples developed ocean-going boats and navigated their way northward through the Bay of Biscay and into the English Channel. At the time, Britain was sparsely populated, home to only a few thousand people. These early settlers were gradually absorbed into much larger migrating groups. The majority of the modern British population today can actually trace their roots back to these Spanish seafarers.”

Over the course of five years, Professor Sykes and his team collected DNA samples from 10,000 volunteers across Britain and Ireland. Their research focused on the Y chromosome—pᴀssed down from father to son—which allowed them to trace paternal lineages deep into prehistory. The results revealed that nearly all participants were descended from one of six distinct Iberian clans that arrived in Britain in several waves before the Norman Conquest in 1066.

The study has major implications for the idenтιтy and origins of the so-called “Celtic” peoples of Britain, including those in Wales, Scotland, Ireland, and Cornwall. Rather than being the product of migrations from central Europe as once thought, it now appears that the Celts are largely the result of prehistoric seaborne migrations from the Iberian Peninsula.

These findings challenge longstanding narratives about British and Irish ethnic origins and suggest a far more complex and seafaring prehistory than previously ᴀssumed. By highlighting the pivotal role of Iberian migrants, the study underscores how ancient maritime technology and migration shaped the genetic landscape of the British Isles.

As Professor Sykes concludes, “Britishness is not purely insular—it’s built on waves of connection, movement, and shared ancestry stretching back thousands of years to the coasts of Spain.