From the early Urnfield culture expanded the Hallstatt culture (ca. 1200-500 BC), associated with Proto-Celtic [Chadwick 1970]. The later expansion of La Tène culture (ca. 500-1st c. BC) from certain core Hallstatt regions – valleys of Marne and Moselle and neighbouring Rhineland in the west, and a Moravian zone in the east – has been linked to the spread of Celtic languages. However, the Mainz research project of bio-archaeometric identification of mobility has not proven to date a mass migration of Celtic peoples in central Europe ca. 4th-3rd centuries BC, i.e. precisely in a period where textual evidence informs of large migratory movements[Scheeres 2014]. La Tène material culture points to far-reaching inter-regional contacts and cultural transfers[Burmeister 2016].
R1b1a1a2a1a2b-U152 lineages are found today, scattered to the north, south, and west of the Alps, reaching the southwest corner of the Iberian Peninsula, and the British Isles. It seems to peak around the current borders between Italy, France, and Switzerland. The first sample of haplogroup R1b1a1a2a1a2b-U152 found in the British Isles (contemporaneous with the first sample found of haplogroup R1b1a1a2a1a1-U106) is from Driffield Terrace ca. 250 AD, after the Roman invasion[Martiniano et al. 2016].
The expansion of I2a2a-M223 lineages, assumed to be already mixed with R1b1a1a2a1a2b-U152 lineages since at least the Tumulus culture, is found from the British isles to Anatolia, with a I2a2a1a1-M284 lineage concentrated in Great Britain (with mutational divergence suggesting its foundation ca. 300 BC) providing “some tentative evidence of ancient flow with eastern areas that could support the idea that the La Tène culture was accompanied by some migration”[McEvoy and Bradley 2010].
The scarcity of R1b1a1a2a1a2b-U152 and I2a2a-M223 lineages in the modern populations of the British Isles and Iberia – where Celtic languages had clearly spread by the time of the Roman invasion – appear to suggest a successful cultural diffusion of the language from warring Celtic minorities who established new chiefdoms throughout Europe. It is also possible that a previous admixture of R1b1a1a2a1a2c1-L21 and R1b1a1a2a1a2a-DF27 lineages in the expanding Celtic population further confounds the genetic change associated with the Celtic expansion.
Lacking ancient DNA samples and more complex genetic analyses, it may be assumed from the available data that the sociocultural phenomenon associated with the expansion of La Tène culture (and Celtic-speaking peoples) is different from the Neolithic expansion of farming – where Anatolian ancestry spread slowly with technology –, and also from the Bronze Age expansion of herding – where male-dominated groups spread rapidly into western Europe and partially replaced or displaced the original population.
- [Burmeister 2016] ^ Burmeister, Stefan. 2016. Archaeological Research on Migration as a Multidisciplinary Challenge. In The Genetic Challenge to Medieval History and Archaeology, edited by W. Pohl and A. Gingrich: Austrian Academy of Sciences Press.
- [Chadwick 1970] ^ Chadwick, Nora. 1970. The Celts. London: Folio Society.
- [Cunliffe and Koch 2012] ^ Cunliffe, Barry W., and John T. Koch. 2012. Celtic from the West: Alternative Perspectives from Archaeology, Genetics, Language, and Literature. Oxford: Oxbow Books.
- [Martiniano et al. 2016] ^ Martiniano, Rui, Anwen Caffell, Malin Holst, Kurt Hunter-Mann, Janet Montgomery, Gundula Müldner, Russell L. McLaughlin, Matthew D. Teasdale, Wouter van Rheenen, Jan H. Veldink, Leonard H. van den Berg, Orla Hardiman, Maureen Carroll, Steve Roskams, John Oxley, Colleen Morgan, Mark G. Thomas, Ian Barnes, Christine McDonnell, Matthew J. Collins, and Daniel G. Bradley. 2016. Genomic signals of migration and continuity in Britain before the Anglo-Saxons. Nature Communications 7:10326.
- [McEvoy and Bradley 2010] ^ McEvoy, Brian P., and Daniel G. Bradley. 2010. Irish Genetics and Celts. In Celtic from the West: Alternative Perspectives from Archaeology, Genetics, Language and Literature, edited by B. Cunliffe and J. T. Koch. Oxford: Oxbow Books.
- [Myres et al. 2011] ^ Myres, N. M., S. Rootsi, A. A. Lin, M. Jarve, R. J. King, I. Kutuev, V. M. Cabrera, E. K. Khusnutdinova, A. Pshenichnov, B. Yunusbayev, O. Balanovsky, E. Balanovska, P. Rudan, M. Baldovic, R. J. Herrera, J. Chiaroni, J. Di Cristofaro, R. Villems, T. Kivisild, and P. A. Underhill. 2011. A major Y-chromosome haplogroup R1b Holocene era founder effect in Central and Western Europe. Eur J Hum Genet 19 (1):95-101.
- [Scheeres 2014] ^ Scheeres, Mirjam. 2014. High mobility rates during the period of the “Celtic migrations”? 87Sr/86Sr and δ18O evidence from Early La Tène Europe, Fachbereich Biologie, Johannes Gutenberg–Universität Mainz, Mainz.
- [Thurston 2009] ^ Thurston, Tina. 2009. Unity and Diversity in the European Iron Age: Out of the Mists, Some Clarity? Journal of Archaeological Research 17 (4):347-423.
- Further information on SNPs by Richard Rocca and Alex Williamson.