It was always going to be this way

The native peoples of the East Baltic — Estonians, Latvians and Lithuanians — are genetically alike and their paternal gene pools are dominated by the same two Y-chromosome haplogroups: R1a and N3a.
Linguistically, however, Estonians are a world apart from Latvians and Lithuanians. That’s because the Estonian language belongs to the Uralic language family, which has an obvious North Eurasian character. On the other hand, Latvian and Lithuanian are both classified as Indo-European languages, along with the vast majority of other European languages.
The Uralic and Indo-European language families may or may not descend from the same ancestral tongue, but even if they do, their relationship is very distant.
So how is it that Estonians came to speak a Uralic language? As far back as I can remember, the basic explanation accepted by most people was that Uralic speech arrived in what is now Estonia and neighboring Finland during the Bronze Age with migrants, or perhaps invaders, rich in N3a from somewhere around the Ural Mountains. Conversely, Latvians and Lithuanians were generally assumed to have retained the Indo-European speech of their R1a-rich forefathers from the Pontic-Caspian steppe, who colonized the East Baltic and surrounds during the Late Neolithic.
Ancient DNA has now uncannily corroborated these theories (for instance, see Mittnik et al. 2018 and, published today, Saag et al. 2019). All it took was a handful of samples from a few relevant sites. I think that’s awesome; I love it when sensible, long-standing hypotheses are validated by cutting edge science.
I’ll have a lot more to say about the spread of Uralic languages and Uralian genes to the East Baltic when I get my hands on the genotype data from the new Saag et al. paper. I also have a post coming soon about the Nordic Bronze Age. Stay tuned.

See also…
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…
Corded Ware people =/= Proto-Uralics (Tambets et al. 2018)
Inferring the linguistic affinity of long dead and non-literate peoples: a multidisciplinary approach
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