Ancient DNA favors an eastern central European route for Celtic languages
A study of 4,587 ancient genomes finds that ancestry linked to Late Bronze Age populations in eastern central Europe spread westward before Celtic languages became widespread.
Editorial illustration — not from the study.
The study analysed genome-wide data from 4,587 ancient individuals, including 752 newly generated genomes, to compare demographic patterns with competing ideas about how Celtic languages spread across prehistoric Europe. It identified several major movements, including Steppe-related ancestry associated with Bell Beaker groups, a later movement from southwestern Europe into Britain, and a westward expansion from eastern central Europe during the Late Bronze Age.
The researchers argue that the eastern central European movement best fits the known demographic history for the spread of a major component of the Celtic languages. This ancestry reached France, Britain, northeastern Iberia and Italy, and later appeared in populations associated with Hallstatt and La Tène contexts.
The westward movement
The researchers identified ancestry associated with the Knovíz subgroup of the Central European Urnfield Culture as forming in the Carpathian Basin between about 4,000 and 3,200 years ago. It then expanded across much of western Europe between about 3,200 and 2,800 years ago, reaching France, the British Isles, northeastern Iberia and Italy. The ancestry persisted into Hallstatt-related populations in France, Germany and Austria, affected Britain by about 2,800 years ago and reached Iberia by about 2,500 years ago.
The study also distinguishes this movement from two earlier population shifts: the arrival of Steppe-related ancestry with Bell Beaker-associated groups after about 4,400 years ago, and a movement from southwestern Europe into Britain between about 3,800 and 3,200 years ago. The researchers conclude that the later movement from eastern central Europe is the most parsimonious explanation for the demographic component associated with the spread of Celtic languages. They do not support explanations that place the main spread in southern France or Iberia, or along the Atlantic seaboard with Late Neolithic Bell Beaker groups.
Why the route matters
Celtic languages were once spoken across much of Europe but are now limited mainly to the Atlantic fringes. Their early homeland and routes of expansion have remained disputed because there is no written record from the period in which they spread.
By identifying a westward population movement from eastern central Europe that preceded or accompanied the appearance of relevant Iron Age populations, the study narrows the demographic scenarios that fit the history of Celtic languages. It supports an eastern central European setting linked to the Urnfield, Hallstatt and La Tène cultural sequences, while showing that earlier movements from the Atlantic region or southwestern Europe do not best match the genetic evidence.
Evidence and caveats
The study uses genome-wide data from 4,587 ancient individuals, including new samples from regions relevant to the debate, and compares shared DNA patterns among individuals. The analysis can identify population movements and ancestry relationships, but it cannot directly show which language people spoke. The authors explicitly note that language shifts do not necessarily track genetic change, and that human history does not always follow the simplest route.
The wider Urnfield Culture is also difficult to assess directly because cremation means that few genomes from it are available; the genomic evidence is strongest for the Knovíz subgroup. The conclusions therefore concern the demographic scenarios most consistent with the available ancient DNA, rather than a direct genetic proof that a particular population spoke Celtic.
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