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Genetics of the Nordic Bronze Age

Bronze Age Scandinavia. Massive burial mounds full of wealth. Groups of armed men with bronze weapons manning boats. Status-obsessed hierarchical warriors and traders. The likeliest candidates for pre-Proto-Germanic speakers and a proto-Germanic material culture. But who were they, and where did they come from?

The people of the Nordic Bronze Age were skilled metalworkers and seafarers. They were expert traders, capable of running extensive trade networks. They were the ancestors of not only the Germanic tribes of the Migration Period, but also of the Vikings. This highly stratified society ruled by an aristocratic elite laid the foundation for much of what would become the Germanic peoples. In order to understand their genetic profile, we have to go back even further in time. Back – to a much more turbulent time. Namely, Neolithic and Chalcolithic Europe.

See also: recent developments in Scandinavian archaeogenetics

Abbreviations

WSH = Western Steppe Herder

WHG = Western Hunter-Gatherer

EHG = Eastern Hunter-Gatherer

CHG = Caucasus Hunter-Gatherer

EEF = Early European Farmer

CWC = Corded Ware culture

BAC = Battle Axe culture

FBC/TRB = Funnelbeaker culture (Trechterbekercultuur )

SHG = Scandinavian Hunter-Gatherer

PWC = Pitted Ware culture

PIE = Proto-Indo-European

NBA = Nordic Bronze Age

PCA = Principal component analysis

LN = Late Neolithic

Autosomal DNA

The Nordic Bronze Age people show clear signs of genetic continuity from the Late Neolithic Scandinavians. This was a genetic profile that had fully formed by 2100 BC in the Southern parts of Norway and Sweden, as well as in Denmark.

The development of the Late Neolithic Scandinavian dagger period, associated with the spread of flint daggers, from Prescott et al. (2012)

The genetic profile of the LN Scandinavians and the NBA people can best be described as a mix of the Battle Axe culture, Single Grave culture, and the Funnelbeaker culture. These three populations met and mingled in Scandinavia. It is possible that they also had small amounts of SHG (Scandinavian hunter-gatherer) ancestry from the Pitted Ware culture. Below, we’ll go through what this actually means and who the people of these ancient populations were.

Pitted Ware culture

In order to understand who the people of the Nordic Bronze Age and the populations ancestral to them were, it’s also important to gain an understanding of who lived in Scandinavia before them. The original inhabitants of Scandinavia were the Mesolithic hunter-gatherers known in archaeogenetics as SHG (Scandinavian hunter-gatherers). The PWC people were their descendants, a group of hardy foragers who were highly adapted to the brutally harsh environment that they had originally settled in around 9,000 years ago. They belonged to the genetic cluster known as SHG which was first identified in six hunter-gatherer individuals from Motala, Sweden, dated to 6000 BC. The SHG were a mix of WHG and EHG, the former having colonized Scandinavia from the south and the latter from the northeast. Just like most Mesolithic (and Neolithic, which was technically the case for PWC) hunter-gatherers of Europe, they existed on a WHG:EHG genetic cline. In some parts of Scandinavia, they were more shifted towards the WHG cluster, while in other parts they had more EHG admixture and were thus more EHG-shifted.

Their diet mainly consisted of seafood and meat, and they were genetically adapted to the cold. This is strengthened by the presence of the protein TMEM131 which is associated with long-term adaptation to cold in SHG DNA samples. Interestingly, this gene is also present in modern day Northern Europeans. Physically they were tall, fit and robust. In terms of Y-DNA, DNA samples from PWC skeletons reveal I2 haplogroups, mainly of the I2a1 branch. This branch was common among earlier SHG from Motala in Sweden, Steigen in Norway, and Hummervikholmen in Norway as well. It is nearly non-existent among present-day Scandinavians. It is possible that present-day Scandinavians have small amounts of ancestry from the PWC. However, results from a study on the topic (Malmström 2009) showed that there isn’t much autosomal continuity between the PWC hunter-gatherers and modern Scandinavians. This suggests that these hunter-gatherers were simply replaced by the incoming groups, such as the Battle Axe Culture. As such, it comes as no surprise that the people of the Nordic Bronze Age do not seem to have significant ancestry from the Pitted Ware culture, which we’ll get to later down below. The idea that modern North Europeans don’t have much autosomal DNA continuity from SHG is not unique to Malmström’s study, I might add. However, Günther et al. (2018) did not make the same conclusion. Instead, this paper proposed that present-day northern Europeans do have some degree of SHG admixture. Another study by Malmström (2015) also hinted at there being at least some autosomal contribution from the PWC to present-day Scandinavians. While speculative, it just might be from the Pitted Ware culture, or from another group of (more northeastern, perhaps) SHG, that Scandinavians get their mysterious I1 Y-DNA haplogroup (but that’s a topic that is complicated enough to deserve its own article.)

There is extensive evidence of PWC being quite a violent culture. Spectacular finds of PWC arrowheads inside human skulls have been made. A study on the topic (Iversen 2016) even found that the PWC had different types of arrowheads, one of which was dedicated solely to warfare instead of hunting. This suggests that for a relatively primitive hunter-gatherer culture, the PWC had a rather sophisticated style of tribal warfare. In addition to that, the hunter-gatherers of the Pitted Ware culture were not very keen on other groups intruding on their territory. Which brings us to the next ancient population that entered Scandinavia…

Funnelbeaker culture

The earliest agriculturalists to ever enter Scandinavia, the Funnelbeaker people were a unique group of people with a real frontier mentality. Agriculture was introduced to Europe by an ancestral genetic group called EEF (Early European Farmers). They entered Europe through Anatolia and formed many different- and for their time – highly advanced cultures. Archeological remains of these cultures can be found in all corners of Europe, from Iberia to Britain, to Poland and Scandinavia. However, it can be said that the places where agriculture had the least success was Scandinavia and what is now the Baltic countries, as well as Finland. The Funnelbeaker people settled Scandinavia from the South, going from Germany to Denmark and the Southern parts of Norway and Sweden. Conditions for the relatively primitive form of agriculture that they practiced were not ideal in this region, especially not in Norway and Sweden. Thus, these early farmers faced many difficulties. This may be the reason why Scandinavians have one of the lowest percentual levels of ancestry from EEF in Europe. In Europe, only the Balts and the Finns carry lower levels of EEF ancestry than Scandinavians do. In terms of Y-DNA, current finds of DNA show that the men of the FBC culture mainly carried haplogroup I2, with a minority of G2a lineages. These Y-DNA lineages are rare among present-day Scandinavians, suggesting that there is little to no male continuity from the FBC but still significant autosomal contribution.

The Funnelbeaker people had a rather different genetic profile than the earliest farmers who entered Europe through Anatolia. Funnelbeaker people often had very high levels of indigenous European hunter-gatherer ancestry. This ancestry component is called WHG (Western Hunter-Gatherer) ancestry and in modern times, it reaches its peak in Baltic people (Estonians, Latvians, Lithuanians) followed by Finns, Basques and Scandinavians, in that order. In some Funnelbeaker individuals, WHG ancestry made up as much as 50% of the total DNA. Interestingly enough, their hunter-gatherer DNA was reflected in their customs, which differed from that of other EEF groups. Funnelbeaker groups were often less sedentary than other early farmers, relying more on hunting and fishing and slightly less on grains to survive. In addition to that, they also herded cattle. Some research has even suggested that the Funnelbeaker culture was where lactose tolerance first evolved in Europe. In the areas previously inhabited by the people of the Funnelbeaker culture, present-day lactose tolerance reaches its peak anywhere in Europe.

There is evidence of the inhabitants of Funnelbeaker settlements building primitive palissades for defensive purposes towards the end of the TRB phase. It has been established that the hunter-gatherers of the PWC may have directed violent efforts against the FBC, and it is even possible that this triggered a re-migration of FBC people out of Sweden and Norway, through Denmark and into North Germany in the late TRB phase. However, the signs of re-migration that we can observe may also have been caused by the difficulties that agriculturalists faced due to the poor soil and hostile terrain in Norway and Sweden. The difficulties and harsh conditions for Funnelbeaker people around the Oslofjord were especially extreme. Being raided by bands of hunter-gatherers probably didn’t make things any better, though!

The FBC people buried their dead in collective megalith graves. The culture existed between 4300 BC-2800 BC.

Skeletal remains from the Funnelbeaker culture have revealed that they were relatively short in stature. They were often mesocephalic, which means that their heads were neither very long nor very short. Round face shapes may have been common among them, likely a result of deriving their ancestry from both robust and wide-faced hunter-gatherers and from more long-faced and gracile Anatolian farmers. While Funnelbeaker remains from Germany tend to resemble the remains of other EEF (especially the ones of the Globular Amphora culture), those from Denmark and Sweden were more robust and only exhibit minor changes from the Mesolithic skeletons in the same area (Bennike 1985, 1993.)

This ancient genetic component is represented by DNA from skeletal remains associated with the Funnelbeaker culture from Poland, Germany and Sweden.

Battle Axe culture

The first Indo-European speakers to enter Scandinavia, the people of the Battle Axe culture were a highly mobile and relatively warlike group. The culture is characterized by their distinctive boat-shaped battle axes made out of flint, which were used as status symbols in burials. The Proto-Indo-European languages are believed to have been introduced to Europe by pastoralists from the Pontic-Caspian steppe, belonging to the Yamnaya culture. Their ancestral DNA component is called the WSH (Western Steppe Herder) component, or sometimes simply the Yamnaya component. The Yamnaya (WSH) were a mix of two populations, EHG (Eastern Hunter-Gatherers) from Eastern Europe, and CHG (Caucasus Hunter-Gatherers) from the Caucasus region. The Yamnaya pastoralists rapidly migrated to Europe and, in most places, replaced the Y-haplogroups of the local men. Offshoots of the Yamnaya culture developed into the Corded Ware culture, which in turn developed into different offshoots. The Battle Axe culture was the Scandinavian offshoot of the Corded Ware culture. The people of the early Corded Ware culture in Poland and Germany were already mixed to some degree with the local EEF people. However, in early CWC individuals, this admixture was not particularly high. As the CWC people entered Scandinavia, their EEF ancestry increased as they mixed with the locals, but remained relatively low. Corded Ware people carried roughly 75% Yamnaya admixture, while modern North Europeans carry about 50% on average. This means that the CWC people plot somewhere in between Yamnaya and North Europeans on a PCA. In terms of Y-DNA, the men of the BAC mainly carried haplogroups R1a, in particular the Scandinavian R1a-Z284 subclade that is common in present-day Norway and Sweden. They likely also carried a minority of R1b and, possibly in the latest phase, I1 lineages.

The Battle Axe culture relied on both cattle herding and agriculture for sustenance. They did not always settle in one place, but consistently moved around across Scandinavia, showing a slight preference for the inland areas as opposed to coastal areas. The BAC burial system involved individual graves, which was a stark difference in comparison to the collective megalith graves of the previous Funnelbeaker culture. Evidence suggests that they were far more individualistic than the more collectivist Funnelbeaker culture. The Battle Axe culture existed between 2800-2300 BC.

Skeletal remains from Battle Axe individuals show that they were a tall and long-limbed people, who were often dolichocephalic. This means that many of them had skulls that were longer relative to their width, and likely rather long faces. The BAC people almost certainly inherited their height from their Yamnaya ancestors. Yamnaya had the highest ever predicted genetic height of any ancient population.

The BAC genetic component is represented by skeletal remains associated with the Battle Axe culture from Sweden.

Single Grave culture

Similar to the Battle Axe culture, the Single Grave culture was an offshoot of the Indo-European Corded Ware culture. The SGC occupied much of the Western part of the European plain, mainly parts of present-day Denmark, Netherlands, and Germany. As the name of the culture implies, the SGC people buried their dead in single graves. These single graves often involved burial mounds. The mounds would contain coffins in which the dead were placed. The kurgans, or burial mounds, have their ultimate origin in the Yamnaya culture of the Pontic-Caspian steppe. The burial mound, sometimes also called tumulus, or kurgan burial type became the standardized type of burial during the Nordic Bronze Age. Especially so among the elites. The SGC practiced basic agriculture and cattle herding.

Genetically, the Single Grave people were fairly similar to those of the Battle Axe culture. Both hailed from the CWC and ultimately, from a Yamnaya-related source population, and thus carried a high percentage of Western Steppe Herder ancestry. Much like other middle phase Corded Ware people, they had about 75% Yamnaya-related ancestry. In terms of Y-DNA, current finds from the SGC are sparse. However, it is likely that they mainly carried various subclades of haplogroup R1b. One male from a SGC burial in Gjerrild carried haplogroup R1b-V1636.

Physically, the SGC people were tall and robustly built. While their skulls were fairly long, the Bell Beaker people who were closely related to the SGC people were notably brachycephalic, meaning that they had skulls that were shorter and wider than typical.

Nordic Bronze Age

So, this finally brings us to the NBA. Seeing as they were a mix of these 3 populations mentioned above, they had unsurprisingly also adopted customs and characteristics from all 3. This involved animal husbandry and herding, agriculture, and hunting, fishing and gathering. Rich archaeological remains from this cultural sphere suggest that the Nordic Bronze Age was a highly prosperous and wealthy culture. Some of the artefacts left behind can even give us an insight into their religion, which has often been suggested to have revolved around the sun, as some sort of solar cult. Take the Trundholm chariot, for example. Just like a lot of other NBA artefacts, it has spiraling patterns. Looking at swords, the same circular solar patterns can be observed. The Trundholm chariot would likely originally have consisted of not one, but two horses. Both horses may have been pulling a representation of the sun. It is possible that the sun-worship served multiple purposes. Not only was it related to crops, harvests and fertility, but possibly also to gold and wealth. The people of the Nordic Bronze Age loved bright metals, and it’s not impossible that this was because gold and bronze reminded them of the powerful and important sun. Now, let’s get into some more details regarding the genetic profile of these sun-worshipping people.

The first study to sequence whole genomes from Nordic Bronze Age individuals (Allentoft 2015) found that the NBA people had a strong genetic affinity to the Corded Ware culture, Unetice culture, and even the Sintashta culture. Nordic Bronze Age people were found to have the highest levels of lactose tolerance among Bronze Age Europeans. There was a strong and relatively drawn out selection for lactase persistence in Northern Europe during this period, as shown in Burger et al., 2020. The Nordic Bronze Age people were tall and, on average, mesocephalic (they had skulls that were neither very long nor very short). In terms of Y-DNA, current samples have yielded haplogroups I1 and R1b. However, the samples thus far are only from southern Sweden and Denmark, causing a slight sample bias. The typically Scandinavian R1a-Z284 will almost certainly be found in remains from the Nordic Bronze Age in future studies, along with other lineages, some of which may not be common today. By the time of the late Neolithic, this Scandinavian trio of Y-DNA lineages had already emerged along with the Nordic_LN genetic cluster that I mentioned in the start of this article. Thus, there is a noticeable continuity from the late Neolithic into the Nordic Bronze Age not just in terms of autosomal DNA, but also when it comes to Y-DNA haplogroups.

Below is a rather simplified Principal Component Analysis (PCA) that I made using the Global 25 tool created by David Wesolowski. What we see is that modern Scandinavians (represented in the PCA as simply “Norwegian, Swedish, Danish”) form a cluster together with the late Neolithic and Bronze Age populations from Sweden and Denmark. They also position themselves very close to populations like Battle Axe and Corded Ware. This cluster has some slight variation, with the Norwegians and Swedes generally being closer in distance to Corded Ware and the Danes being closer to the Danish Bronze Age individuals, simply due to the slightly higher EEF component among Danes and the slightly higher Yamnaya component among Norwegians and Swedes. If we were to add the Danish Single Grave culture sample from Gjerrild, he would position himself nicely alongside the rest of the Scandinavian cluster.

Scandinavian cluster highlighted in the circle
Useful albeit slightly outdated WHG:WSH:EEF ancestry proportions in Europeans, from Haak et al. (2015)

I have added the RUS_Sintashta_MLBA population average (represented by DNA from likely proto-Indo-Iranian speakers, from the steppe) simply because of the proposed cultural Sintashta or Sintashta-like influence on the Nordic Bronze Age culture. The earliest known chariot has been found in a Sintashta culture burial, and these were the people of the culture that developed into the Andronovo culture and likely invaded India, bringing with them their language and culture. The cultural similarities between these Corded Ware-derived cultures can be observed in Nordic Bronze Age artefacts such as the Trundholm chariot from Denmark. As can be seen in the PCA, Scandinavians do show some very minor affinity towards Steppe_MLBA populations like Sintashta. However, this is not due to direct admixture, but simply due to shared ancestral components. The modern populations closest to Sintashta would be various Eastern European populations. As such, the visual “closeness” of Scandinavians to Sintashta on this PCA is the result of what’s called artificial distance. Sintashta, just like Scandinavians, largely had their origin in a Corded Ware culture population, but Scandinavians, both Bronze Age, Iron Age and modern, can better be described as post-CWC populations due to having a higher EEF component.

The Pitted Ware culture (SWE_PWC_NHG on the PCA) is positioned in the upper right corner, closest to modern Finnish and Baltic individuals, which is due to their higher hunter-gatherer admixture. Bear in mind, however, that the genetic distance between the PWC and any modern population is rather massive, and not even Balts and Finns can be said to be genetically “close” to them. Continuing, the PCA seems to show the same thing that Malmström 2009 concluded, which is that Bronze Age, Iron Age and modern Scandinavians do not derive much of their total ancestry from the PWC. Rather, present-day Scandinavians have a very high genetic affinity to the Corded Ware populations of Scandinavia, the Czech Republic, Germany and Poland. We can examine, to some extent, how much Corded Ware ancestry modern Scandinavians have by creating an admixture model in G25. For the sake of accuracy, let’s use scaled coordinates. As proxies for their ancestral components, we can use Polish Corded Ware samples and Swedish Funnelbeaker samples. Below are models for Norwegians, Swedes and Danes. Observe that we are able to model Scandinavians as approximately 70% Corded Ware and 30% Funnelbeaker. However, it should be kept in mind that there is signifcant WHG ancestry in both the Polish Corded Ware as well as Swedish Funnelbeaker sample averages.

What’s interesting is that if we add a Pitted Ware component (SWE_PWC_NHG) that actually improves the fit for Swedes, but not for Norwegians. With that model, Swedes show 3.2% SHG admixture, 70.2% Corded Ware admixture, and 26.6 Funnelbeaker admixture. For Norwegians, no PWC admixture seems to be able to be detected and their admixture model remains as 71.4% Corded Ware and 28.6% Funnelbeaker. Future samples may be able to improve the fit for these admixture models and provide better references for potential SHG contributors, as well.

Unetice culture migrants and haplogroup R1b-U106: A contributing cultural and genetic factor to the Nordic Bronze Age?

The Unetice culture was a wide-spanning, advanced and influential Central European Bronze Age culture. It left behind impressive artefacts such as the well-known Nebra Sky Disc. It has been speculated that the decline and collapse of Unetice caused some of its people to migrate north. These hypothetical migrants perhaps brought new technology, especially related to metallurgy, to the more geographically remote lands of the north. However, current DNA evidence is unable to prove this. There have been theories circulating about immigrating groups rich in Y-DNA R1b-U106 from Central Europe/Unetice to Scandinavia just prior to the beginning of the Nordic Bronze Age. While it’s not impossible that there was such an immigration, the ancient DNA record has shown no evidence of it as of yet. With that said, current finds of R1b-U106 dating to the Late Neolithic and Bronze Age are quite sparse and available DNA evidence on this topic may drastically change with future discoveries.

On the contrary, it’s not impossible that there was some immigration from Late Neolithic Scandinavia southwards to Unetice. Let’s examine that possibility. First off, isotopic evidence from a 2013 study showed proof of migration from Sweden to Poland during the early Central European Bronze Age. Dr Anna Pokutta at Gothenburg University wrote about this in her doctoral thesis called “Population Dynamics, Diet and Migrations of the Unetice Culture in Poland“. The isotopic analysis she highlighted showed a male-biased migration from Sweden into the Unetice culture in the early Central European Bronze Age. Now, if we backtrack just a little bit, back to haplogroup R1b-U106. Ancient DNA samples of R1b-U106 are relatively few at the moment, but the oldest sample is currently PNL001 (Papac et al. 2021) who was found in an early Corded Ware culture setting in the Czech Republic. The sample is dated to roughly 2900 BC. After PNL001, there is something of a gap in samples until the second oldest R1b-U106 sample, which is indeed sample RISE98 from Skåne, Sweden (Allentoft et al. 2015). RISE98 is dated to 2431-2238 BC and was archaeologically given a cultural assignment to the Scandinavian Late Neolithic culture. Given that it is in this context we find the earliest R1b-U106 sample in Scandinavia, this does to some extent speak in favour of an immigration out of Scandinavia to the Unetice culture like the one proposed by Pokutta, but it does not necessitate it. In any case, it certainly proves that the U106 branch was already present in Scandinavia before the Unetice collapse took place and subsequent migration happened, and may even have arrived in Scandinavia with early Corded Ware groups. It is most likely, however, that it first arrived in Scandinavia alongside Late Neolithic migrations from the Single Grave culture, starting at roughly 2500 BC.

Leaving Y-DNA aside for a moment, let us have a look at autosomal DNA. Unetice individuals had ancestry proportions of Yamnaya/WHG/EEF in similar percentages that modern North Europeans do. If we look at where the combined average of Unetice individual samples end up, it’s right inside the aforementioned Late Neolithic Scandinavian, Bronze Age and modern Scandinavian cluster. If we use G25 to calculate genetic distance to modern populations we can see that the Polish Unetice average, German Unetice average, and the Czech Unetice averages all show affinity towards present-day Scandinavians (likely due to artificial distance as a result of similar ancestry proportions, however).

Given that the more northern-shifted Unetice samples seem quite similar to Late Neolithic Scandinavians, the combination of the previously mentioned factors could imply that there were population movements from Scandinavia into the Unetice culture. However, the opposite could still also be true, as this was a period of high mobility. Late Neolithic Nordic populations were so genetically similar to the more steppe and HG-shifted parts of the population of the Unetice culture that in the scenario of a migration from Unetice into Scandinavia, we would not necessarily be able to tell that any migration had taken place. The only way to really determine this is if future DNA studies go into further detail regarding specific Y-DNA subclades of Late Neolithic populations in, for example, Denmark, while also focusing on strontium isotope ratios.

In summary, there is currently no way to say with certainty that there was a migration of Unetice people into Scandinavia just prior to the beginning of the Nordic Bronze Age. If there was, it’s likely that this would have been quite a small group of high-status individuals, likely bringing new metallurgy and other pieces of technology. What we can safely say is that there was at least some migration from Scandinavia into the Unetice culture during the early Central European Bronze Age.

Conclusion

To summarize, the people of the Nordic Bronze Age had a high degree of genetic continuity from the Late Neolithic people of Scandinavia. Future DNA studies will give us further insight into specifics regarding Y-DNA subclades of the NBA people, as well as clearing some things up in regards to the significant increase in frequency that haplogroups I1 and R1b-U106 underwent in Scandinavia in the Nordic Bronze Age. There are some very interesting ongoing research projects that will examine topics like continuity from the Nordic Bronze Age stretching to the Viking Age, as well as the DNA of more high-status Nordic Bronze Age burials. This is sure to be interesting, but may take a while!

For the most up-to-date information about aDNA from the Nordic Bronze Age, see From Stone to Bronze in prehistoric Scandinavia.

References:

Luka, Papal et al. (2021): Dynamic changes in genomic and social structures in third millennium BCE central Europe https://advances.sciencemag.org/content/7/35/eabi6941

Burger, Joachim (2020): Genomic Data from an Ancient European Battlefield Indicates On-Going Strong Selection on a Genomic Region Associated with Lactase Persistence Over the Last 3,000 Years https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3565013

Günther, Torsten ((2018): Population genomics of Mesolithic Scandinavia: Investigating early postglacial migration routes and high-latitude adaptation https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2003703

Allentoft, Morten (2015): Population genomics of Bronze Age Eurasia https://www.nature.com/articles/nature14507

Malmström, Helena (2019): The genomic ancestry of the Scandinavian Battle Axe Culture people and their relation to the broader Corded Ware horizon https://royalsocietypublishing.org/doi/10.1098/rspb.2019.1528

Haak, Wolfgang (2015): Massive migration from the steppe was a source for Indo-European languages in Europe https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5048219/

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Malmström, Helena (2015): Ancient mitochondrial DNA from the northern fringe of the Neolithic farming expansion in Europe sheds light on the dispersion process https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4275881/

University of Gothenburg (2013): Proof of human migration from Sweden to Poland during the Bronze Age https://www.sciencedaily.com/releases/2013/10/131007094247.htm

Iversen, Rune (2016): Arrowheads as indicators of interpersonal violence and group identity among the Neolithic Pitted Ware hunters of southwestern Scandinavia https://www.sciencedirect.com/science/article/abs/pii/S0278416516301350

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