Can we know if our ancestors were Vikings? The short answer is yes, we can. DNA testing may trace Viking background in our genetic makeup. However, Nordic ancestry cannot be proven or disproven in all cases. A few years ago, when I first got interested in genetic genealogy, I thought that there might be some sort of Norse gene that all Vikings transmitted to all their descendants as a heritage. So you are either positive or negative for it. However, it’s not that simple. This tutorial will explain it all about genes and genetic testing for those who’d like to find out if they have Viking roots.
First of all, different nations do not have different genes. To be sure, there are groups of people with specific genetic traits but the borders between these groups do not coincide with borders of what we now define as nations. Moreover, Vikings were not a nation. Vikings were people who a) took part in raids directed from Scandinavia and Scandinavian colonies; b) spoke Old Norse; c) shared Norse values and culture; d) all this between AD 793—1066.
Ethnically, Vikings were not the only ancestors of people whom we now call Danes, Norwegians, and Swedes. For instance, Iceland, perhaps the most important Norse colony, has a strong Celtic element, and not only because Vikings often took wives with different ethnic background. Research shows that the genetic makeup of about a quarter of males in Iceland (inherited through the direct male line) may be defined as British/Irish (in terms of geography). It means that many Viking males might have been Celts.
Before we proceed any further, I have to expressly state that no nation is better than any other nation and no genetic traits are better than any other genetic traits, including those that may indicate the presence of Viking background. Matriarchal lineages are as unique as male forefathers. We are all equal in gods’ eyes.
Nordic Ancestry DNA Basic Theory and Terminology
So having Viking ancestry, among other things, means a person is a descendant of someone who was born in Scandinavia. However, with respect to our genes, there is no such thing as “stemming from Scandinavia”. We all stem from Africa. But some of us have ancestor lines that passed through Denmark, Norway or Sweden at some point in time. We’re interested in those who did so during the Viking Age (AD 793—1066). In order to understand what genetic markers may help us find out if one has Viking ancestry, we are to delve into some theory and terminology.
Genetic information is carried by DNA. DNA is the main component of chromosomes.
Males have one Y chromosome and one X chromosome. Females have two X chromosomes.
Y chromosome contains information about all the changes that occurred to it in a given direct male line up to the very first human male. These changes are called mutations. In genetic genealogy two types of mutations are relevant: STR and SNP (pronounced snip).
STRs (short tandem repeats) occur rather often (in terms of generations). STR profiling uniquely identifies a person (except for identical twins). STRs define your haplotype.
SNPs (single-nucleotide polymorphisms) occur not so often as STRs. The set of SNP mutations define your haplogroup. Subsets within haplogroups are called subclades.
There are 20 major Y chromosome haplogroups designated by letters from A through T.
Viking Background Haplogroups
The most important haplogroup that may be a strong predictor of Viking genetic background is I1. But also R1a, R1b, G2, N, and a few others may well point to your Viking roots.
SNP that defines I1 haplogroup is M253.
It is critical to understand that not all Vikings were I1 and not all I1 were Vikings. I1 was a modification of I that emerged about 27,000 years ago. To be sure, no Vikings were anywhere to be seen at that time. How come it is now believed to predict your Nordic ancestry?
Modern Scandinavians essentially belong to I1, R1a and R1b. Haplogroup R1a is found in a lot of other places like Poland, Russia, Ukraine, Belarus, Slovakia, Latvia, Lithuania and so on. R1b is also prominent in Ireland, the Scottish Highlands, western Wales, the Atlantic coast of France, the Basque country and Catalonia. I1 is so peculiar because it is thought to be concentrated for a very long time almost exclusively in Scandinavia. Chances are the present-day bearers of I1 outside Scandinavia got it from Norsemen that resettled from their homeland. The only place where I1 massively appeared before the Viking Age outside prdent-day Norway, Sweden and Denmark, was Finland.
The best place to hunt for Viking genetics is UK. Indeed, we know that several waves of Viking settlers colonised large portions of Britain during the Viking Age. Since British Isles are not the place where I1 appeared initially, modern people with I1 from localities with names of Norse origin in UK have good chances to be the posterity of the Viking Age Scandinavians who came to live in Danelaw. Many of them might have been Vikings (but some of them might well have been thralls, too).
You may ask how we can tell if modern I1 don’t have ancestors who came to Britain with earlier waves of migration? After all, Angles and Jutes who invaded Britain in the 5th century were also from Scandinavia. And how to tell both groups from I1 who peacefully lived in Finland for the last 5,000 years or so? The answer is: subclades.
Subclades That Point to Viking Genetics
Haplogroups have subgroups called subclades. Subclades are branches within haplogroups defined by consecutive new mutations. For a regularly updated complete I1 haplogroup tree with all subclades check this page. Mutations occur once in a certain number of generations. Comparing various genetic profiles, the emergence of some mutations could be located in time and space. This allows to associate certain subclades with Viking activities in various parts of Europe. Here are some subclades that may be pointing to Norse roots outside Scandinavia:
I-Y17395 — Scotland.
I-M227 — Baltic countries, Russia, Poland, France and southern England.
I-Y18103 — Poland, Slovakia, Hungary, and Russia.
I-S10891 — Normandy and Britain.
I-Y4045 — England and Ireland.
I-Y3664 — Schleswig-Holstein, Normandy and Guernsey.
I-Y5621 — Normandy and Britain.
I-L813 — Britain.
R1a-Z284 — Scotland, England and Ireland.
Among others, Tom Hanks was found to belong to R1a-Z284.
How to Order DNA Test for Viking Ancestry
A good place to start would be learning your haplogroup. This can be done through testing for Y-DNA STR markers. STRs do not directly define haplogroups (SNPs do) but STRs can be used to predict your haplogroup with a high degree of certainty. The more markers are tested, the higher is test quality. Standard sets are 37, 67 and 111 markers. In certain genetic projects also sets of 12 and 25 markers may be tested. The more markers are tested, the higher the price. For the comparison chart, see this page. You may also be eligible for free testing. For the list of projects that offer free tests see this page. I did the testing for 111 markers with Family Tree DNA. My experience with them was very positive.
If you order tests from FTDNA, be sure to join their Viking & Invader YDNA project and make your results available to the project administrators. They may be of help as for understanding your results and choosing what to do next.
To learn your exact location on the haplogroup tree, you should test for SNPs, which is a lot more expensive. This will define your exact subclade. The results of SNP testing are extremely complex to interpret for non specialists, so many people were disappointed after ordering it as for what they actually got. Based on my own experience (I did Big Y testing with FTDNA, which is now marketed as Big Y-700), the most effective use of SNP testing results is uploading them to YFull. To do that, you will need BAM file. They also receive VCF files but you’ll get only limited functionality. The service costs $49. What they do is comparing your genetic profile (both STRs and SNPs) with lots of other people. Looking at how distant in time your common ancestors are and what places these people are from, chances are you will get a much clearer idea about your roots than you ever have had.