The funerary rituals in Viking Age Scandinavia are known by their complexity and diversity including inhumation, boat burials, and cremation. Cremations have been extensively studied macroscopically, but the application of geochemical techniques, although highly informative to investigate cremation in more detail, have not been widely explored yet. In the Viking Age the inclusion of both animals and humans on the funeral pyres makes research challenging. In the present study, we demonstrate the usefulness of molecular analysis (ATR-FTIR), direct mercury analysis (DMA) and analytical colour (in the CIELab space) for the characterization of Viking Age cremated remains of a human individual buried with dogs, a horse, a cat, and other animals – as well as evaluate macroscopic methods for assessing the temperature of burning. We demonstrate that the spectroscopic signal is highly correlated with analytical colour parameters, and with mercury concentration (still present in bones exposed at high temperatures). Mercury concentration was higher in human bones than animals’, suggesting an ante-mortem exposure. Human bones were probably heated at temperatures between 900 and 1100 °C, while animals were cremated at lower temperature. We also identified a secondary cremation in a layer previously interpreted as a badger burrow. A new Mid Infrared index (MIR-index, TPV), is proposed, and we suggest that the cyanamide band is related to oxygen availability during burning. For the macroscopic method, we recommend splitting the white colour category into two based on bone porosity, to better qualify higher temperatures.

Sexing the skeletal remains of young individuals is crucial yet notoriously difficult in archaeology. Children, who cannot be reliably sexed morphologically, are often excluded from gender-related research, limiting our understanding of past childhood. This issue is compounded in contexts lacking grave goods, such as early Christian burials. We conducted genomic screening of 142 individuals from Sweden dating from the late Viking Age to the Medieval period, including 68 subadults and 74 adults from 27 single and 50 multiple burials. To investigate the treatment of children in death and the role of collective graves, we applied genomic sexing and kinship analyses to individuals from three sites. Contrary to the assumption that collective burials reflect close kinship, our results show that children interred with adults rarely shared close biological ties. Burial patterns indicate that gender roles were established early, with both boys and most girls mirroring adult spatial patterns. However, flexibility existed, and extended kinship likely played a central role in structuring these communities.

Abstract Two archaeological cultural complexes; the Neolithic Funnelbeaker culture (FBC) and the Pitted ware culture (PWC), coexisted on Gotland for over 500 years, between ~3300 and 2800 calBCE. The ancestry of the FBC farmers and PWC marine foragers largely aligns with European Neolithic Farmers and European Mesolithic foragers, respectively, but the direct interactions between the groups on Gotland is not understood. We present a Middle Neolithic (MN) high-coverage genome and a Late Neolithic (LN) low-coverage genome from the Ansarve FBC dolmen. We investigate ancestry, admixture, and pathogens among these MN farmers (n = 6), foragers (n = 19), and the LN individual. We find that recent gene-flow between farmers and foragers could have taken place, although most gene-flow happened prior to their coexistence on the island. We also find evidence of different Yersinia pestis strains in the three cultural groups, showing that the pestis was widespread among groups with different subsistence strategies.

The earliest morphologically identifiable dogs are from Europe and date to at least 14,000 years ago1-5, although early remains are also found in other regions. The origin of early dogs in Europe, and their relationships to other dogs, has remained elusive in the absence of genome-wide data. Similarly, although dogs were the only domestic animal to predate agriculture, little is known about how the arrival of Neolithic farmers from Southwest Asia affected the dogs living with European Mesolithic hunter-gatherers. Here we analysed 216 canid remains, including 181 from Palaeolithic and Mesolithic Europe. We developed a genome-wide capture approach that enriched endogenous DNA by 10-100-fold and could distinguish dog from wolf ancestry for 141 of 216 remains. The oldest dog data that we recovered are from a 14,200-year-old dog from the Kesslerloch site in Switzerland, and we find that it shares ancestry with later worldwide dogs-inconsistent with the hypothesis that European Upper Palaeolithic dogs derived wholly from a separate domestication process. The Kesslerloch dog already displays more affinity to Mesolithic, Neolithic and present-day European dogs than to Asian dogs, demonstrating that dog genetic diversification had started well before 14,200 years ago. We find a Neolithic influx of Southwest Asian ancestry into Europe, but this seems to have been of smaller magnitude than in humans, suggesting that Mesolithic dogs contributed substantially to Neolithic, and, ultimately, probably also modern, European dogs.

Kin relations among past societies can offer valuable information about the social dynamics of the population. Genetic data from prehistoric human remains can reveal genetic relatedness, and when combined with archaeological information, shed light on social factors shaping ancient communities. However, accessing such information on ancient hunter-gatherer societies has been challenging owing to the scarcity of temporally overlapping multi-burial sites. Here, we focused on the Pitted Ware Culture (PWC) cemetery from Ajvide (Gotland, Sweden), one of Stone Age Europe's largest and best-preserved hunter-gatherer burial grounds of the European Stone Age. We generated new genomic data from 10 individuals, primarily from co-burial contexts, and combined these with published genomes from 24 individuals across four PWC sites on Gotland. The genetic analyses revealed dual ancestry of the Gotlandic PWC, showing approximately 80% ancestry associated with earlier Mesolithic hunter-gatherer groups and 20% with farmer groups. We also identified close genetic relatives between the different studied PWC sites on Gotland, indicating mixing of the groups. All individuals buried together were closely related to one another, including first-, second- and third-degree relatives, and showed significantly elevated genetic relatedness. This demonstrates that genetic relatedness played a defining role in the co-burial ritual and extended beyond first-degree relatives.

Dogs were domesticated at least once from a yet-unidentified wolf population at least ~15,000 y ago. However, how domestication took place is a topic of ongoing debate, and the ability of human groups to manage wolves in their communities during early stages of domestication is poorly understood. Here, we report multiproxy data from two canids excavated from Late Neolithic and Bronze Age contexts in the Stora Förvar cave on the island of Stora Karlsö in the Baltic Sea. The island is small (2.5 sq km) and, like the neighboring island of Gotland, carries no endemic populations of terrestrial mammals. Instead, the current consensus is that human introductions account for some mammal fauna on Gotland, and for the majority of that on Stora Karlsö. Genome-wide data show that the two canids have ancestry indistinguishable from Eurasian wolves, with no shared ancestry with domestic dogs of the Canis familiaris lineage. Their genome-wide heterozygosity is lower than that observed in 72 previously published ancient wolf genomes, and instead comparable to dogs. Stable isotope data (δ13C and δ15N) reveals a diet rich in marine protein, which is consistent with habitation alongside the human groups who used Stora Karlsö as a seal-hunting, fowling, and sea fishing station, and in the Bronze Age probably also for grazing. Skeletal size is at the lower end of wolf variability, and one individual shows advanced pathology consistent with reduced mobility. While other scenarios are possible, a parsimonious explanation is that these wolves were brought to the island by humans and were possibly under human control.

In the period between 5,300 and 4,900 calibrated years before present (cal. bp), populations across large parts of Europe underwent a period of demographic decline1,2. However, the cause of this so-called Neolithic decline is still debated. Some argue for an agricultural crisis resulting in the decline3, others for the spread of an early form of plague4. Here we use population-scale ancient genomics to infer ancestry, social structure and pathogen infection in 108 Scandinavian Neolithic individuals from eight megalithic graves and a stone cist. We find that the Neolithic plague was widespread, detected in at least 17% of the sampled population and across large geographical distances. We demonstrate that the disease spread within the Neolithic community in three distinct infection events within a period of around 120 years. Variant graph-based pan-genomics shows that the Neolithic plague genomes retained ancestral genomic variation present in Yersinia pseudotuberculosis, including virulence factors associated with disease outcomes. In addition, we reconstruct four multigeneration pedigrees, the largest of which consists of 38 individuals spanning six generations, showing a patrilineal social organization. Lastly, we document direct genomic evidence for Neolithic female exogamy in a woman buried in a different megalithic tomb than her brothers. Taken together, our findings provide a detailed reconstruction of plague spread within a large patrilineal kinship group and identify multiple plague infections in a population dated to the beginning of the Neolithic decline. Population-scale ancient genomics are used to infer ancestry, social structure and pathogen infection in 108 Scandinavian Neolithic individuals from eight megalithic graves and a stone cist, showing that Neolithic plague was widespread.

Prehistoric chewed pitch has proven to be a useful source of ancient DNA, both from humans and their microbiomes. Here we present the metagenomic analysis of three pieces of chewed pitch from Huseby Klev, Sweden, that were dated to 9,890–9,540 before present. The metagenomic profile exposes a Mesolithic oral microbiome that includes opportunistic oral pathogens. We compared the data with healthy and dysbiotic microbiome datasets and we identified increased abundance of periodontitis-associated microbes. In addition, trained machine learning models predicted dysbiosis with 70–80% probability. Moreover, we identified DNA sequences from eukaryotic species such as red fox, hazelnut, red deer and apple. Our results indicate a case of poor oral health during the Scandinavian Mesolithic, and show that pitch pieces have the potential to provide information on material use, diet and oral health.

With the Neolithic transition, human lifestyle shifted from hunting and gathering to farming. This change altered subsistence patterns, cultural expression, and population structures as shown by the archaeological/zooarchaeological record, as well as by stable isotope and ancient DNA data. Here, we used metagenomic data to analyse if the transitions also impacted the microbiome composition in 25 Mesolithic and Neolithic hunter-gatherers and 13 Neolithic farmers from several Scandinavian Stone Age cultural contexts. Salmonella enterica, a bacterium that may have been the cause of death for the infected individuals, was found in two Neolithic samples from Battle Axe culture contexts. Several species of the bacterial genus Yersinia were found in Neolithic individuals from Funnel Beaker culture contexts as well as from later Neolithic context. Transmission of e.g. Y. enterocolitica may have been facilitated by the denser populations in agricultural contexts.

The input of strontium from aquatic resources in an omnivorous diet has been researched to a lesser degree than that of terrestrial sources, which, in specific sociocultural settings, complicates the study of provenance and mobility. To address this lack of research and to investigate forager mobility in an archipelago environment, where access to terrestrial resources was limited and earlier studies have indicated a dependence on marine resources, we targeted the mid-Neolithic hunter-fisher-gatherers from the site Jettböle on the Åland Islands. Using laser ablation multi-collector inductively coupled plasma mass spectrometry, we analysed the 87Sr/86Sr ratios in the enamel of human and dog teeth and contextualized the data with bioavailable Sr measurements from various water and animal enamel sources. The results show that utilization and consumption of aquatic resources have had a major impact on the Sr ratios of both humans and dogs from Jettböle. The data indicate significant differences from the local terrestrial bioavailable Sr ratios, even if the studied individuals likely grew up in the area. Our results suggest that investigations of Sr isotope ratios may be especially challenging for PWC individuals and other coastal living groups. By comparing both Sr ratios and the sequential measurement pattern from the investigated subjects to other human groups and animals it has, nevertheless, been possible to offer a tentative interpretation of both the origin and mobility patterns of humans and dogs from Jettböle. Most of the individuals may be suggested to have originated, and subsided on a diet, from within the Åland archipelago. It is also possible that some of the studied individuals moved there from different regions.

Harp seals (Phoca groenlandicus), once present in the Baltic Sea, now stand extinct. During the Middle Neolithic period, they held significant dietary importance for the Pitted Ware Culture hunter-fisher-gatherers in Scandinavia. Because they are no longer available for ecological studies, little is known about their specific behavioural intricacies, such as diet, mobility, and reproductive strategies. Because of the seal's pivotal role in these human societies and because they provide an interesting ecological case study on post-isolation ecological adaptation to new environmental conditions, a comprehensive investigation into Baltic Sea harp seal behaviour is warranted.In this pursuit, we employ sequential analysis of strontium isotope ratios (87Sr/86Sr) in harp seal teeth sourced from archaeological contexts across three study regions. This data is harmonized with osteometric analyses from fifteen archaeological sites from the Baltic Sea area, establishing a methodological framework for comprehending the Sr isotopic pathway in a brackish water inland sea. By adopting this approach, we unveil breeding and mobility patterns of the long-extinct Baltic Sea harp seals, approximate specific breeding areas connected to each group of seals and delve into the ontogenic temporal frame governing these observed patterns. This endeavour culminates in an enriched understanding of the adaptive behaviours exhibited by Baltic Sea harp seals and equips us with the insights necessary to decipher the lifestyle of the human societies intricately intertwined with them.

In 2021, we published the results of genomic analyses carried out on the famous bishop of Lund, Peder Winstrup, and the mummified remains of a 5–6-month-old fetus discovered in the same burial. We concluded that the two individuals were second-degree relatives and explored the genealogy of Peder Winstrup to further understand the possible relation between them. Through this analysis, we found that the boy was most probably Winstrup’s grandson and that the two were equally likely related either through Winstrup’s son, Peder, or his daughter, Anna Maria von Böhnen. To further resolve the specific kinship relation, we generated more genomic data from both Winstrup and the boy and implemented more recently published analytical tools in detailed Y chromosome- and X chromosome-based kinship analyses to distinguish between the competing hypotheses regarding maternal and paternal relatedness. We found that the individuals’ Y chromosome lineages belonged to different sub-lineages and that the X-chromosomal kinship coefficient calculated between the two individuals were elevated, suggesting a grandparent–grandchild relation through a female, i.e., Anna Maria von Böhnen. Finally, we also performed metagenomic analyses, which did not identify any pathogens that could be unambiguously associated with the fatalities.

Sheep are among the earliest domesticated livestock species, with a wide variety of breeds present today. However, it remains unclear how far back this diversity goes, with formal documentation only dating back a few centuries. North European short-tailed (NEST) breeds are often assumed to be among the oldest domestic sheep populations, even thought to represent relicts of the earliest sheep expansions during the Neolithic period reaching Scandinavia <6,000 years ago. This study sequenced the genomes (up to 11.6X) of five sheep remains from the Baltic islands of Gotland and Åland, dating from the Late Neolithic (∼4,100 cal BP) to historical times (∼1,600 CE). Our findings indicate that these ancient sheep largely possessed the genetic characteristics of modern NEST breeds, suggesting a substantial degree of long-term continuity of this sheep type in the Baltic Sea region. Despite the wide temporal spread, population genetic analyses show high levels of affinity between the ancient genomes and they also exhibit relatively high genetic diversity when compared to modern NEST breeds, implying a loss of diversity in most breeds during the last centuries associated with breed formation and recent bottlenecks. Our results shed light on the development of breeds in Northern Europe specifically as well as the development of genetic diversity in sheep breeds, and their expansion from the domestication center in general.

In this paper, we investigate the Scandinavian Late Neolithic and Early Bronze Age of Kinnekulle in southwestern Sweden. The above-mentioned periods in the study area are poorly understood and the archaeological record consists of a few stray finds and a concentration of 20 gallery graves. This study focuses on three of the gallery graves where commingled skeletons from successive burials were recovered. The human remains and the artefacts from the graves were used for discussing individual life stories as well as living societies with the aim of gaining new knowledge of the last part of the Neolithic and the beginning of the Early Bronze Age in southwestern Sweden. We focused on questions concerning health and trauma, mobility and exchange networks, and diet and subsistence of the people using the graves. Chronological, bioarchaeological, and biomolecular aspects of the burials were approached through the application of archaeological and osteological studies, as well as stable isotope, strontium isotope, radiocarbon, and mtDNA analyses. The study provides evidence for high mobility and diverse diets, as well as inhumations primarily dated to the transition between the Late Neolithic and Early Bronze Age. We suggest that the mountain plateau of Kinnekulle was mainly reserved for the dead, while the people lived in agriculture-based groups in the surrounding lower lying regions.

We investigate a 2,000-year genetic transect through Scandinavia spanning the Iron Age to the present, based on 48 new and 249 published ancient genomes and genotypes from 16,638 modern individuals. We find regional variation in the timing and magnitude of gene flow from three sources: the eastern Baltic, the British-Irish Isles, and southern Europe. British-Irish ancestry was widespread in Scandinavia from the Viking period, whereas eastern Baltic ancestry is more localized to Gotland and central Sweden. In some regions, a drop in current levels of external ancestry suggests that ancient immigrants contributed proportionately less to the modern Scandinavian gene pool than indicated by the ancestry of genomes from the Viking and Medieval periods. Finally, we show that a north-south genetic cline that characterizes modern Scandinavians is mainly due to the differential levels of Uralic ancestry and that this cline existed in the Viking Age and possibly earlier.

The genomic landscape of Stone Age Europe was shaped by multiple migratory waves and population replacements, but different regions do not all show similar patterns. To refine our understanding of the population dynamics before and after the dawn of the Neolithic, we generated and analyzed genomic sequence data from human remains of 56 individuals from the Mesolithic, Neolithic, and Eneolithic across Central and Eastern Europe. We found that Mesolithic European populations formed a geographically widespread isolation-by-distance zone ranging from Central Europe to Siberia, which was already established 10,000 years ago. We found contrasting patterns of population continuity during the Neolithic transition: people around the lower Dnipro Valley region, Ukraine, showed continuity over 4000 years, from the Mesolithic to the end of the Neolithic, in contrast to almost all other parts of Europe where population turnover drove this cultural change, including vast areas of Central Europe and around the Danube River.

We present a spatiotemporal picture of human genetic diversity in Anatolia, Iran, Levant, South Caucasus, and the Aegean, a broad region that experienced the earliest Neolithic transition and the emergence of complex hierarchical societies. Combining 35 new ancient shotgun genomes with 382 ancient and 23 present-day published genomes, we found that genetic diversity within each region steadily increased through the Holocene. We further observed that the inferred sources of gene flow shifted in time. In the first half of the Holocene, Southwest Asian and the East Mediterranean populations homogenized among themselves. Starting with the Bronze Age, however, regional populations diverged from each other, most likely driven by gene flow from external sources, which we term "the expanding mobility model." Interestingly, this increase in inter-regional divergence can be captured by outgroup-f3-based genetic distances, but not by the commonly used FST statistic, due to the sensitivity of FST, but not outgroup-f3, to within-population diversity. Finally, we report a temporal trend of increasing male bias in admixture events through the Holocene.

The grey wolf ( Canis lupus ) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage ( Canis familiaris ) lived 1 – 8 . Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000–30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.