Strontium data shows that Aldaieta remains are mostly local Basques - but some immigrants too

Certain historians have in the past claimed that Southern Basques arrived from the North in the Middle Ages (Spanish school) or vice versa, that Northern Basques arrived from the South in exactly the same period (French school). The evidence for either hypothesis was nearly zero but that does not seem to deter certain kind of minds more concerned about defending their own biased version of history than about knowing and discussing the facts.

Your truth not, Truth.
And come with me in search of it,
yours keep it for yourself.

Antonio Machado

Luis Ángel Ortega et al., Strontium isotopes of human remains from the San Martín de Dulantzi graveyard (Alegría-Dulantzi, Álava) and population mobility in the Early Middle Ages. Quaternary International 2013. Pay per view → LINK [doi:10.1016/j.quaint.2013.02.008]

Abstract

Strontium isotope analysis of human remains from San Martín de Dulantzi (Alegría-Dulantzi, Álava, Spain) graveyard has been used to establish mobility patterns during the Early Middle Ages. Some archaeological human remains had Germanic grave goods. Through radiogenic strontium isotope analysis, local origin individuals and immigrants were differentiated. Archaeological human bone samples exhibit 87Sr/86Sr = 0.70779–0.70802 values similar to domestic fauna isotope composition, indicating local origin of individuals or long residence time in the region. Comparing these data with tooth enamel values, two groups of immigrants from distinctive geological environment were established. The Dulantzi population constituted mainly a local society with influxes of immigrants. The foreign individuals are distributed through the studied period of time, suggesting that migration movements were limited in number. Isotopic signatures indicating mainly local individuals, linked to grave goods with archaeological attribution to Germanic origin, question the previous ethnic paradigm.

Fig. 7. Isotope variation of the studied samples. Grey area corresponds to the variation range in local waters (Fernández de Ortega, 2007). Dashed line indicates the average isotope ratio of soil at the site. Doted line corresponds to the average for the bones. Green and blue areas indicate immigrants from different geological environments.

At the time of writing this entry, Luis Ortega had uploaded a pre-print version of the paper at Academia.edu.

The site was argued to imply immigration because of the grave goods (pottery, weapons, belt buckles), which are similar to those found elsewhere in the Basque Country in that period and which are much more similar to Frankish or Aquitanian similar items than to Iberian ones (then under Visigothic rule). The period of the cemetery includes the 6th and, much more densely, 7th centuries CE.

Duchy of Vasconia, 8th century (CC by myself)

The Duchy of Vasconia was founded by the Merovingian Franks in 602 as a march against Basque tribes, then effectively independent. In 628 Charibert, brother and heir of Dagobert, was appointed as Duke after the successful Basque rebellion of 626, and in 635 a massive Frankish army took control of most of the country but defeated in Zuberoa (Soule). Another rebellion in 643 erased all Frankish control and established an independent state, since 660 in personal union with Aquitaine (in medieval times the romanized area between the Garonne and the Loire with capital in Toulouse).

Meanwhile the Visigoths of Toledo had established another march by the name of Duchy of Cantabria in the southern frontier, briefly conquering what is now Southern Navarre in 621 and founding the city of Oligitum (Olite). The fact that the Bishop of Pamplona was absent from Visigothic Councils at Toledo between 589 to 684 evidences that the Goths never conquered anything relevant further North than this town.

With this historical context it seems somewhat logical that Southern Basques had greater relations with the Franks and, particularly, the wider region of Aquitaine (both Novempopulania, now Gascony and the Northern Basque Country, and medieval Aquitaine between the Garonne and the Loire), however nothing seems to suggest widespread immigration.

Neither do the results of this study, which however show half a dozen individuals apparently from outside (two groups).

It is interesting to recall that a previous study on ancient mtDNA on the same cemetery (Alzualde 2006, PPV - but available at Academia.edu), found three individuals with the lineage U2 and two with M1c, both apparently exotic in the Basque Country. U2 is relatively common (5%) in the area of Perigord-Limousin (Dubut 2004), while M1c is deemed North-West African. However the vast majority of lineages belongs to haplogroups normal among Basques since early Neolithic times, and in apportions consistent with local continuity.

However the similitude between Basque and Aquitanian genetic pools does not allow for easy discernment, reason why this isotopic study is particularly important to confirm the local origins of most of the Aldaieta medieval population.

Thanks to Ama Ata[es], which made me aware of this study.