They came, they saw, and they mixed

Y-chromosome haplogroup N is strongly associated with Uralic-speaking populations. That’s probably because it was a salient feature of the gene pool of the earliest Uralic speakers, and it went with them as they migrated across northern Eurasia. However, some of its younger subclades appear to have spread with the speakers of Indo-European and Turkic languages.
For instance, N-Y10931 seems to be a marker of the Rurikids, a Varangian dynasty that, according to most sources, ruled the Kievan Rus in what are now Russia and Ukraine. And the Kievan Rus was a lose medieval political federation in which Slavic, Finnic (west Uralic) and Germanic languages were probably spoken. The latest on the genetic genealogy of the Rurikids was presented a couple of days ago at the Centenary of Human Population Genetics conference in Moscow, and there’s an abstract of the talk available here (download the PDF and scroll down to page 84).
I’m not aware of any Rurikids among the thousands of ancients in my dataset, or even of any samples belonging to N-Y10931. However, I do have the genome of someone who belongs to N-Y4339, which, as per the abstract linked to above, is proximally ancestral to N-Y10931. Not only does this person come from Viking Age Scandinavia, but he was buried in a crouched position typical of Slavic funerary customs of the time.
The individual in question is vik_84001. His genome was published recently along with a paper on the population structure of the Swedish town of Sigtuna way back when it was a Viking stronghold (see here). This is where his Y-chromosome sequence, labeled ERS2540883, is positioned on the YFull Y-chromosome phylogenetic tree. Click on the image to go to YFull.

However, the result is likely to be compromised to some extent by missing data. If so, it’s possible that vik_84001 does indeed belong to N-Y10931 and ought to be sitting near or even among that cluster of Russian samples (Rurik descendants?) at the bottom of the page.
In any case, vik_84001 seems to be the closest individual in the ancient DNA record to a Rurikid. The Principal Component Analysis (PCA) below is based on my Global25 test. It features 13 other Viking Age individuals from Sigtuna alongside vik_84001 (look for the black dots). Interestingly, despite his eastern Y-haplogroup, vik_84001 is one of the few Sigtuna ancients who clusters strongly with present-day Swedes.

But here’s what happens when I model his ancestry proportions with the Global25/nMonte method using a wide range of reference populations from Northern and Eastern Europe. The Swedes in this model are the same as those in the PCA.

vik_84001
Swedish,84.6
Ingrian,9.2
Russian_Tver,6.2
Belarusian,0
Estonian,0
Finnish,0
Finnish_East,0
Karelian,0
Latvian,0
Mordovian,0
Russian_Kostroma,0
Russian_Kursk,0
Russian_Orel,0
Russian_Pinega,0
Russian_Smolensk,0
Russian_Voronez,0
Ukrainian,0
Vepsian,0
[1] «distance%=2.3778»

Yep, despite his position in the PCA, vik_84001 shows a strong signal of ancestry related to the present-day populations of northwestern Russia. I’m not sure what this means exactly, but it’s certainly fascinating stuff. And, by the way, I usually wouldn’t use so many similar reference populations in a single Global25/nMonte model because of the problem of «overfitting», but in some cases it’s OK to do so if the nMonte algorithm has enough recent genetic drift to latch onto.
See also…
More on the association between Uralic expansions and Y-haplogroup N
Fresh off the sledge
Uralic-specific genome-wide ancestry did make a signifcant impact in the East Baltic
It was always going to be this way
Conan the Barbarian probably belonged to Y-haplogroup R1a

Source