Callanish Stones, Isle of Lewis, built by Neolithic farmers, one of the contributors to Scottish genetics
The development of genetic studies has brought on our understanding of human movements in history and prehistory forward by leaps and bounds, as well as that of the relative closeness and distance between different groups of people. While there are still many missing links and questions which remain unanswered, we know enough by this point to be able to tell which modern-day and historical groups of people are descended from whom. We have abundant evidence for Britain in particular, so I am proud to present a more-or-less complete summary of Scotland's genetic history. While such a subject may be intimidating to those unfamiliar with it, I will try my best to keep it understandable and engaging, as there is much to be gained from discovering what genetic studies have to tell us.
One of the benefits of looking at such subjects is because, sadly, national origin myths have often been constructed to suit social or political narratives (which may not even be known to us any more). For example, the Scots have always been held in historical texts (such as the Declaration of Arbroath) to have originated in Scythia (nowadays the southern parts of Russia and Ukraine) and to have come to Ireland via Iberia (before settling in Scotland in post-Roman times). We know based on the genetic studies that the first part of that story is true, but the idea that they came through Iberia is not (the details of which I will explain below). Therefore, the study of ancient DNA (aDNA), or 'archaeogenetics', can help us cut through distortions that have been added to a people's national history using purely scientific means.
The Declaration of Arbroath, in which the Scots argued their unique ethnic origin in Scythia, their journey through the Mediterranean to Spain, then to Ireland and their present home, precluded them being ruled by England
While there are many ways to interpret aDNA, one of the most intriguing and informative are 'haplogroups', which are genetic markers carried by people which trace direct paternal or maternal descent. The former are derived from the Y-chromosomes of men (Y-DNA) and so are only carried by men, while the latter are drawn from mitochondrial DNA (mtDNA) and are carried by everyone. It is on haplogroups specifically that I want to focus here, as they give us the best indications pertaining to direct descent, which is important if you want to study the origins of populations ('autosomal admixture', that is, tracking the relative closeness of population groups, is not as relevant, but still helps us in working out the extent to which populations were replaced by others and will be referred to at points).
Our story begins following the Ice Age, when Britain was colonized by hunter-gatherers (part of the genetic group known as 'Western Hunter-Gatherers' or 'WHGs'). While we now have evidence that Scotland was inhabited during the Palaeolithic, we only have genetic samples from Scotland in the period after the Ice Age. So far, the only Mesolithic sample we have from Scotland is from Cnoc Coig, Isle of Oronsay (next to the Isle of Colonsay), of a woman who carried mtDNA haplogroup V, which is nowadays most common among the Sami of Northern Scandinavia and Russia, followed by the Cantabrians of Northern Spain1. However, most other WHGs typically carried mtDNA haplogroup U, such as other examples from Britain like Cheddar Man.
The most recent reconstruction of Cheddar Man from Somerset, his eye, skin and hair color is based on the presence or absence of genetic markers determining these traits
When it comes to Y-DNA, none of the haplogroups found among hunter-gatherers from England survive today, but a specific related subclade (branch) of Cheddar Man's haplogroup is known as 'I2-M284', which, while it has not yet been found among Mesolithic Britons, is only ever found in Britain from archaeological samples later than the Mesolithic and overwhelmingly in Britain in modern times; this suggests that I2-M284 is indigenous to Britain. Fascinatingly, some of the highest rates of I2-M284 in the world occur in Scotland2. This means that it is likely about 5% of men in Argyll and the Borders (perhaps less in the rest of Scotland) are the direct descendants of her earliest inhabitants3.
I must state at this point that, unfortunately, this article will disproportionally focus on the male lineages, as mtDNA haplogroups are much more dispersed among many population groups and are much more difficult to track. For instance, any given mtDNA haplogroup may be found in two very different places, so it would then be difficult to tell which group it was brought with. In contrast, Y-DNA haplogroups tend to appear in clusters, attesting to the settlement of groups of closely related men, in contrast to women who typically came from a wider variety of lineages. This seems to indicate different patterns of migration between men and women, but for now we must be content mostly with what we can tell from the Y-DNA.
However, one instance in which the information from mtDNA is very clear is that the maternal lineages of the WHGs in Britain were replaced by those of incoming farmers in the Neolithic ('Early European Farmers' or 'EEFs'), whose ultimate origins lay in Anatolia, now Turkey. Interestingly, most of the British EEFs carried haplogroup I2-M284 (an all so far found carried I2), which suggests that the EEF settlement was primarily driven by women and entailed bringing local hunter-gatherer men into their communities (the EEFs carried such mtDNA haplogroups as H, HV0, J, K, T, W and X). The farmers then began to cut down the forests, which the hunter-gatherers had relied upon for their resources, to create arable land for their crops. They were responsible for the great megalithic monuments such as Callanish on Lewis and Maes Howe on Orkney.
Maes Howe, Orkney, a Neolithic chambered cairn
Unfortunately for the farmers on mainland Britain, they appear to have outstripped their resources and their population crashed. A unique culture developed on Orkney which suggests the beginning of hierarchy among British EEFs, which subsequently spread across the east coast of Britain and even as far as Southern England. This potential colonization is characterized by the great 'henge' monuments and the presence of a specific pottery style known as 'Grooved Ware'. However, the stage was set for the most impactful migration, one from whom the majority of Scotsmen today are descended from: that of the Western Steppe Herders ('WSHs'), who introduced the Bronze Age to Britain4.
The WSHs were mainly descended from a group known as 'Eastern Hunter-Gatherers' ('EHGs'), who lived in what is now Western Russia and Ukraine, who picked up the practice of herding animals from their neighbors in the Caucasus (and some of their women too, judging by some of the mtDNA haplogroups and admixture of the WSHs which came from the Caucasus). Maternally-speaking, the EHGs were very similar to the WHGs, also mostly carrying haplogroup U. However, their Y-DNA was very different: most of them carried haplogroup R1. The R1b subclade is most relevant for our story, because not only was it most likely the original WSH haplogroup, but it it is now the most common haplogroup in Western Europe, with 72.5% of Scotsmen carrying it5.
In particular, one culture developed on the steppe that proved crucial to the proliferation of the WSHs, known as 'Yamnaya'. They learned the art of bronzeworking, once again from their Caucasian neighbors, and dominated the steppe. Some folk from the Yamanya culture mixed with EHGs further north (who more typically carried haplogroup R1a, now most common in Eastern Europe and parts of Asia), giving rise to the Corded Ware culture, which began to spread westward into what is now Germany. However, one specific branch of R1b known as 'P312' split from Corded Ware and adopted a type of pottery originating in Iberia, which is known as 'Bell Beaker'. It is specifically the L21 branch of R1b-P312 that is responsible for colonizing the British Isles, which it seems to have done from the Netherlands, bringing with it Bell Beaker pottery and bronze.
The Yamnaya and Corded Ware cultures, R1b (and some R1a) followed the arrow pointing west, while the north-west and eastward expansions represent movements by R1a tribes
L21 is still the most common subclade of R1b in Scotland, Ireland, Wales and Brittany (all historically Celtic-speaking countries), but is nowadays less common in England, where R1b-U106 is more often found (while some has been found in Bronze Age, Iron Age and Roman Britain, this suggests that not all of it arrived in Britain with the Anglo-Saxons and Danes, though most of it likely did, as it was rare in earlier time periods). While the Bronze Age and Iron Age saw migration to other parts of Britain, Scotland largely remained the realm of the descendants of the Beaker folk6 (though some North-West German pottery appeared in North-East Scotland at the beginning of the Iron Age, which seem likely to have been brought by migrants).
R1b-DF13, the most common subclade of L21, which is carried by the vast majority of Irishmen and most Scotsmen, Welshmen and Bretonmen
The next significant migrations to Scotland would have taken place after the Romans (as the Romans staged a purely military occupation and would have left no noticeable genetic legacy on Scotland); namely that of the Scots in the 5th Century and Anglo-Saxons in the 6th or 7th Century. The Scots are hard to distinguish from the Picts (and indeed the very idea of a significant migration of Irish to Argyll has been questioned), as both groups mainly carried R1b-L21 (however, the M222 subclade likely emerged in Ireland and may perhaps be the only haplogroup that could be considered 'Scottish' rather than 'Pictish' in origin).
R1b-U106 and I1, two haplogroups most associated with Germanic peoples, are found in South-East Scotland at similar rates to North-East England7. These are the two most common haplogroups in Scotland after R1b-L21, so they reflect the fact that Anglo-Saxon settlement was extensive in the South-East and that they likely expanded west and north within Scotland beginning in the early 12th Century, so that the ratio of R1b-L21 to these Germanic haplogroups runs on a north-west to south-east cline, though L21 is still the most common haplogroup in Scotland as a whole.
The Anglo-Saxon Kingdom of Northumbria at her greatest extent, although actual colonization of Dumfries & Galloway and Cumbria was likely minimal compared to further east
One last migration which affected Northern Scotland was that of the Norse from the 9th Century onwards, which can be tracked not only by R1b-U106 and I1, but also by R1a, which is more common in Norway than in any other Germanic country. They primarily colonized the Isles, those that settled closest to Ireland eventually adopted Gaelic culture and language through intermarriage with local women. Subsequent migrations to Scotland have not left such a substantial impact on Scotland, mainly consisting of elite movements (such as the Normans) or urban immigration (especially Flemings) that would not have left as much of a substantial impact as the migrations of folk looking for pasture or farmland.
The Hebrides are known in Gaelic as Innse Gall meaning 'Isles of the Foreigners', the foreigners being the Norse; Galloway is also named after 'Foreign Gaels' or Gall-Ghàidheil, indicating colonization by Irish folk with Norse heritage
Overall, only a minority of Scots are descended from British hunter-gatherers, while the largest share of Scotsmen are descended from the Beaker folk (who likely introduced or developed the earliest form of Celtic language), with a significant minority descended from the Anglo-Saxons and Norse and a smaller share descended from medieval immigrants (and perhaps also some Early Iron Age German immigrants). The legacy of the Neolithic farmers likely persists in Scotland's mtDNA, though again, it is very difficult to tell how many mtDNA haplogroups derive from the EEFs, WSHs or even the WHGs; as examples of the most common mtDNA haplogroup in Scotland, H, have been found among all those populations at varying levels.
So what of Bede's assertion that the Picts ended up in Ireland, before the Irish sent them to Scotland but gave them wives? Or that the Irish themselves (and their Scottish descendants) arrived in their island from Iberia? It is difficult to verify these myths with genetic studies, as the general pattern seems to be that the largest of migrations to Scotland (Bell Beaker and Anglo-Saxon) came from the east (except of course the migration of the Scots themselves from Ireland). The only instances where it seems valid to assert migration to Scotland via the Atlantic would be during the Neolithic or the Mid-Late Bronze Age, a time when the British Isles were part of the 'Atlantic Bronze Age' horizon, trading with Gaul and Iberia. Or perhaps in the Mid Iron Age, when cist burials were introduced to Western Britain from Brittany.
Perhaps this implies that the male migrations (which are much easier to trace) primarily came from the east or south-east, while a certain portion of the women (we cannot say how many) may have arrived from the south-west. An origin myth whereby the Gaels originated in Scythia, but arrived in Ireland via Iberia may have been an attempt to reconcile multiple origins into one for the Gaelic race (as all Irishmen are said to have been descended from one paternal lineage in Irish genealogies, which cannot be true when one follows the haplogroups). There are connections between Ireland and Iberia in Bell Beaker times, as wrist-guards/bracers found in Ireland are of a type only found in Southern rather than Central Europe, while an earring or pendant found in Ireland has its closest counterparts in Portugal8. However, it seems difficult to substantiate the claim that the Picts came to Scotland via Ireland, as beakers from North-East Scotland have their closest affinities to the Netherlands9.
In this way, national origin myths can be seen as ways of fusing together multiple origins for a people into a single origin for whatever reason. Was it to maintain social cohesion? To prevent disunity in the face of foreign invasion? Either way, while such myths undoubtedly contain grains of truth, the fact is that we may only understand the true origins of our ancestors by studying their genetics. Hopefully, I have given you a good idea of how much we genetically take from each of the historic migrations, and you too may have tested your own genes to see which group in particular you yourself directly descend from.
3This figure was arrived at using information from https://www.eupedia.com/europe/Haplogroup_I2_Y-DNA.shtml & https://www.yfull.com/tree/I-M284/
4Olalde, I. et al. 2017: The Beaker Phenomenon and the Genomic Transformation of Northwest Europe
6Patterson, N. et al. 2021: Large Scale Migration into Britain during the Middle to Late Bronze Age, Nature
8Manco, J.: 2015, Blood of the Celts
9Cowie T. & Shepherd I.A.G. in Edwards K.J. & Ralston I.B.M.: 2001, Scotland After the Ice Age, p.156