The legendary and the genetic don’t necessarily disagree. Tubal, son of Japheth, and descendants were noted for their skill with metal. The dominant haplotype of Ireland, Wales, scottish highlanders, etc. traces through Bronze Age areas noted for metallurgy.

History has long maintained that the Anglo-Saxon overtaking of the Iron Age Celts was the origin of the British people. Celtic Britain reconstructs the peopling of Britain through a study of genetics, climatology, archaeology, language, culture, and history and overturns that myth and others. The Anglo-Saxons, who supposedly conquered the Celts, contributed only five to ten percent of the British gene pool. The Atlantic Celts, long believed to have migrated to Britain from Central Europe around 300 BC during the Iron Age, can be linked genetically to the people of Basque country. And linguistic evidence suggests that, besides Celtic languages, a Germanic-type language similar to Norse was also spoken in Britain long before the arrival of the Anglo-Saxons.
In this groundbreaking study, Stephen Oppenheimer explaines the surprising roots of the present-day cultural identities of the English, Irish, Scottish, and Welsh.