Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 1 Introduction In 2009, a burial pit containing an assemblage of at least 51 adult male individuals was discovered during the construction of a road at Ridgeway Hill, north of Weymouth, Dorset, Southern England (Fig. 1) No datable artifacts were found associated with the pit; however, at the time of discovery it was believed to be of possible late Iron/early Roman Age, reused during the 10th century. All of the men had been decapitated, with the skulls and mandibles deposited in a pile at the southern edge of the pit, while the postcranial remains were deposited, apparently with little care, on top of one another across the rest of the pit (Loe et al. 2014). All of the skulls were male, and many appeared to be young adults with a few older males, and this interpretation is supported by evidence from the postcranial remains that 70% were classified as under the age of 25. Thirty-four skulls have evidence of sharp-force trauma, in many cases showing multiple injuries (Loe et al. 2014). A Boat Load of Vikings? Carolyn A. Chenery1, Jane A. Evans1,*, David Score2 , Angela Boyle2 , and Simon R. Chenery3 Abstract - The isotope composition of tooth enamel and associated dentine and lead concentration was analyzed for strontium and oxygen (enamel) and carbon and nitrogen (dentine) from ten skulls taken from a burial pit found on the Chalk at Ridgeway Hill north of Weymouth, Dorset, on the south coast of England. These individuals are a subset of the 51 men in this pit, all of whom had been decapitated. The results from the ten individuals show that they were a diverse group of individuals. ATMS radiocarbon dating of three individuals gave dates that are statistically consistent and their weighted mean, when calibrated, provides a date range of AD 970–1025 (93% probability). The oxygen isotope composition ranges between 13.7‰ SMOW and 16.5‰SMOW, which result in drinking-water values between -15.4‰ SMOW and -9.2‰ VSMOW using the adapted Levinson calculation. They were raised in a climate that is colder than that of Britain, and one man has a signature that is consistent with an Arctic origin. The 87Sr/86Sr isotope signature is also diverse, ranging between 0.71013 and 0.72051. Whereas the high value is typical in areas of ancient cratonic rocks underlying much of Scandinavia, the lower values are less diagnostic and could indicate either a coastal origin or a childhood spent in an area underlain by geologically younger rocks. The dietary signature derived from C and N stable isotope analysis is more consistent with a Scandinavian than British diet for the period. Very low concentrations of lead (Pb) in these individuals indicates that lead was not bioavailable to the extent it was in contemporaneous Britain. We speculate that this group of men might represent the crew of a Scandinavian Viking raiding party that was captured and executed by local inhabitants from the Weymouth area. Viking Settlers of the North Atlantic: An Isotopic Approach Journal of the North Atlantic 1NIGL, BGS Keyworth, Nottingham, NG12 5GG UK. 2Oxford Archaeology, Janus House, Osney Mead, Oxford, OX2 0ES UK. 3BGS, Keyworth, NG12 5GG, UK. *Corresponding author - je@nigl.nerc.ac.uk. 2014 Special Volume X:XX–XX Figure 1. Location map of Weymouth and Ridgeway Hill, Dorset, UK. Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 2 The skulls and skeletons exhibit evidence of multiple blows to the jaw, cranium, and vertebrae with a large, very sharp weapon such as a sword. The group is the result of a single execution event during the time of frequent Viking raids along the south coast of England (Loe et al. 2014). The skeletal remains provide an opportunity to examine the lead concentration and isotope composition and diversity of this group and assess their origins and perhaps comment on reasons for their execution. Isotope background Strontium, oxygen, and carbon and nitrogen isotopic systems, reflect local geology (Sr), climate (O), and diet (C and N), respectively. Oxygen and strontium isotope compositions are fixed in enamel biogenic phosphate at the time of tooth formation (Hillson 1996, Hoppe et al. 2003, Price et al. 2002). As strontium and oxygen isotopes behave independently of one another, they provide two variables for investigating an individual’s place of origin and migration patterns (Evans et al. 2006). Carbon and nitrogen isotopes are major constituents of collagen which is found in bone and dentine. Collagen in bone turns over at varying rates, depending on the type of bone and the age of the individual, whereas the isotope composition of collagen in dentine is more or less fixed at the time of formation (Sealy et al. 1995). Oxygen isotopes Oxygen isotopes (δ18O) are derived primarily from ingested fluids and indirectly reflect the isotopic value of available meteoric/ground/drinking water (Daux et al. 2008, Levinson et al. 1987). Drinking water is ultimately derived from meteoric water, and the oxygen isotope value varies according to geographical and climatic factors—particularly temperature, altitude, and distance to the coast (Dansgaard 1964, Daux et al. 2008, Kohn 1996, Longinelli 1984, White et al. 1998). The isotopic value of ground waters varies systematically across the UK from higher on the west coasts to lower in the east (Darling et al. 2003). A similar pattern with more extreme values exists for Western Europe (IAEA 2006, Lecolle 1985, Longinelli and Selmo 2003), and the Eastern Mediterranean follows a similar trend (Lykoudis and Argiriou 2007). Oxygen isotopes (as well as other light, stable isotopes such as D/H, C, and N) are subject to several stages of metabolic fractionation, from drinking water to body fluids and again from body fluids to bio-phosphates (bone and tooth enamel). This fractionation is fairly well understood and predictable, thus allowing the calculation of drinking-water values to assist in determining an individual’s place of origin (Daux et al. 2008, Levinson et al. 1987, Longinelli 1984). The overall δ18O isotope range for UK ground/ drinking water ranges between -9.0‰ and -4.5‰SMOW (Darling et al. 2003). The mean expected value for the Weymouth area is -6.5‰ and range for Southern Britain is between -6.0‰ to -7.0‰SMOW. Proxie drinking-water oxygen isotope values are not available for the Medieval warm pariod and the time of the Weymouth burials. However, northern hemisphere reconstructions by Mann et al. (2008), Moberg et al. (2005), and Mann and Jones (2003) indicate that temperatures for the period AD 1000 to 1100 were “... similar to those observed in the twentieth century before 1990” (Moberg et al. 2005). Strontium isotopes Strontium isotopes (87Sr/86Sr) in the body tissues are derived from food and directly relate to the geology of the area where the food was produced (Bentley 2006, Evans et al. 2006, Montgomery et al. 2005). Strontium isotopes, unlike oxygen, carbon, and nitrogen, are not fractionated by metabolic functions. The Ridgeway Hill site lies on chalk but is within 7 km of Weymouth centre, which is situated on London clay. The biosphere map of Britain (Evans et al. 2010) suggests that individuals raised locally at Ridgeway Hill will have childhood tooth enamel values between 0.708–0.709 for anyone raised specifically on chalk, and between 0.709–0.710 if raised on the nearby London clay. Hence, the best estimate of a local signature is between 0.708 and 0.710 based on these two dominant lithologies. Carbon and nitrogen isotopes Isotope analysis of carbon (δ13C) and nitrogen (δ15N) in collagen provide evidence for sources of dietary intake—plant carbohydrates (fruits, vegetables, and grains) and animal protein (meat, fish and milk products), respectively (Sealy 2001). Nitrogen isotopes primarily provide information about position in the food chain, as each step up the food chain (trophic level) entails a fractionation of 3–5‰ from diet to consumer (Hedges and Reynard 2007). Thus, in general, the higher the nitrogen isotope values the greater consumption of animal protein. A significant consumption of marine protein will be reflected in higher δ15N values (Fischer et. al. 2007, Müldner and Richards 2007). Due to different photosynthetic pathways, different plant types can be distinguished by their isotope values. C4 plants (usually tropical grasses such as maize, millet, or sugarcane) have higher Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 3 carbon isotope values than C3 plants (almost all other grains, fruits, and vegetables). A high consumption of marine foods would also results in higher carbon isotope values than would be expected from non-marine consumers from the same location/region. Materials and Method For the purpose of identifying childhood place of origin and evidence of migration, oxygen and strontium isotopes from the enamel of second adult molars (M2s) were analyzed for each of the 10 individuals. The enamel of M2s represent early childhood (3–7 yrs). To assess the childhood diet of these individuals, carbon and nitrogen isotopes were analyzed in collagen extracted from the dentine of the same teeth subjected to oxygen and strontium isotope analysis. Lead-concentration analyses were carried out on enamel to determine cultural lead exposure. In addition, bone from three individuals were sent to the SUERC Radiocarbon Facility for dating. Tooth sample preparation Each tooth was cut in half using a flexible diamond- edged rotary dental saw. The half selected for analysis was cleaned ultrasonically for five minutes in high-purity water and rinsed twice to remove loosely adhered material. A tungsten carbide dental burr was used to abrade off the enamel surface to a depth of >100 microns. Secondary dentine was removed and discarded, and the enamel and primary dentine were separated. The dentine was reserved for carbon and nitrogen analyses, and the enamel was prepared for oxygen and strontium analysis as described below. Strontium isotope analysis In a clean laboratory, the enamel samples were washed in acetone and cleaned twice, ultrasonically, in high-purity water to remove dust and impurities. They were dried and weighed into pre-cleaned Teflon beakers. Each sample was mixed with 84Sr tracer solution and then dissolved in Teflon-distilled 16M HN03. The sample was then converted to chloride and taken up in 2.5M HCl. Strontium was collected using conventional, Dowex® resin ion-exchange methods. The Sr isotope composition and concentrations were determined by thermal ionization mass spectroscopy (TIMS) using a Thermo Triton multicollector mass spectrometer. Samples were run at c 5V using single Re filaments loaded using TaF following the method of Birck (1986). The international standard for 87Sr/86Sr, NBS987, gave a value of 0.710227 ± 0.000007 (1σ, n = 26). All strontium ratios have been corrected to a value for the standard of 0.710250. Strontium procedural blanks provided a negligible contribution. Lead-concentration analysis The elemental Pb concentrations of the enamel samples and quality-control materials were determined using an Agilent quadropole ICP-MS instrument. The instrument was calibrated using a series of synthetic chemical solutions diluted from multielement stock solutions (SPEX Certprep®), and the calibration was validated using synthetic chemical standards from a separate source (Schroeder et al. 2013). The digest solutions were diluted such that the calcium concentration was between 100 and 200 ppm, optimal for long-term instrument stability, beta detection limits, and all elements falling within the defined calibration range. The reproducibility of the lead-concentration data is ±10% (2σ). Oxygen isotope analysis Biogenic phosphate was converted to silver phosphate (Ag3PO4) using a method based on (O’Neil et al. 1994) and is briefly summarized here. The core enamel samples were crushed to a fine powder and cleaned in hydrogen peroxide for 24 hours to remove organic material. The peroxide was evaporated to dryness, and the sample was then dissolved in 2M HNO3. The sample solutions were transferred to clean polypropylene test tubes, and each sample was treated with 2M KOH followed by 2M HF to remove Ca from the solution by precipitation. The following day, the samples were centrifuged, and the solution was added to beakers containing silver amine solution, and precipitated silver phosphate was filtered, rinsed, and dried. Approximately 0.36-mg aliquots of Ag3PO4 were weighed into silver capsules for analysis. Analytical measurement was by continuous flow isotope ratio mass spectrometry (CFIRMS) using the method of Vennemann et al. (2002). The instrumentation is comprised of a thermo chemical elemental analyser (TC/EA) coupled to a Delta Plus XL isotope ratio mass spectrometer via a ConFlo III interface, all by Thermo Finnigan. All reported isotope ratios are expressed using the delta (δ) notation in parts per thousand (permil: ‰) relative to a standard: δ(‰) = ([Rsample/Rstandard] - 1) x 1000 The reference material NBS120C, calibrated against certified reference material NBS127 (assuming δ18O of NBS127 = +20.3‰ versus Standard Mean Ocean Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 4 Water [SMOW]), has an expected value of 21.70‰ (Chenery et. al. 2010). Each sample was analysed in triplicate. The mean internal mass spectrometry reproducibility was ± 0.13‰ (1σ, n = 3) for this set of analyses and 0.21‰ (1σ, n = 3) for the batch control (external reproducibility of the full chemical procedure). Throughout this paper, drinking-water values are derived using the Levinson equation (δ18Ow = [δ18Op - 19.4] / 0.46; Levinson et al. 1987) modified to take into account a -1.4 method bias correction between Ag3PO4 and BiPO4 (see Chenery et al. 2010). Carbon and Nitrogen analysis of collagen The samples were prepared following a modified Longin method (Brown et al. 1988), described briefly below. Approximately 30–100 mg of dentine was covered with 8 ml of cold 0.5-M HCl to demineralize. The remaining solid collagen was rinsed and solubilized in a solution of pH 3 HCl at 70 ºC in a hot block for 48 hours. The solutions were then filtered using an 8-μm Ezze filter to remove solids before freeze drying. Three 0.6-mg aliquots from each collagen sample were weighed into small tin capsules for analysis. Analysis of carbon and nitrogen isotopes was by CFIRMS. The instrumentation is comprised of an elemental analyser (Flash/EA) coupled to a ThermoFinnigan Delta Plus XL isotope ratio mass spectrometer via a ConFlo III interface. All reported isotope ratios are expressed using the delta (δ) notation in parts per thousand (permil: ‰) relative to a standard: δ(‰) = ([Rsample/Rstandard] - 1) x 1000 Collagen carbon and nitrogen isotopes ratios (δ13C and δ15N) are reported in per mil (‰) relative to Vienna Pee Dee Belemnite (vPDB) and ambient inhalable reservoir (AIR) standards, respectively. δ13C and δ15N ratios were calibrated using an in-house reference material M1360p (powdered gelatine from British Drug Houses) with expected delta values of -20.32‰ (calibrated against CH7; IAEA 2006) and +8.12‰ (calibrated against N-1 and N-2; IAEA 2006) for C and N, respectively. The 1σ reproducibility for mass spectrometry controls were δ15N = ±0.06‰ and δ13C = ±0.06‰ (1σ, n = 15) in this batch of analysis and δ15N = ±0.10‰ and δ13C = ±0.06‰ (1σ, n = 3) for the batch control (external reproducibility of the full chemical procedure). All isotope data are presented in Table 1, and all errors are given at 1σ except where stated otherwise. Results Radiocarbon dating ATMS radiocarbon dating of three individuals gave the following results. A right tibia from a partial skeleton (3698) produced a date of AD 890–1030 (95.4% probability, GU-19115, 1055 ± 40 BP). A midshaft of left fibula (skeleton 3804) produced a date of AD 970–1050 plus AD 1080–1160 (95.4% probability, SUERC-27335, 1005 ± 30 BP). A second midshaft of left fibula (skeleton 3763) produced a date of AD 890–1020 (95.4% probability, SUERC-27339, 1090 ± 30 BP). The three dates are statistically consistent, and their weighted mean when calibrated provides a date range of AD 970–1025 (93% probability). This result places the age of the pit within the Saxon period broadly in the reign of Aethelred the Unready (AD 978–1016). Oxygen isotopes Oxygen isotope data for each tooth is presented in Table 1 and plotted against Sr isotope composition in Figure 2. The δ18Op range for this group is between +13.7‰ SMOW and +16.6‰ SMOW. The calculation of drinking-water values for this range of Table 1. Isotope data from teeth taken from 10 skulls from a burial pit found on the Chalk at Ridgeway Hill north of Weymouth, Dorset, on the south coast of England. A = adult, YA = young adult. Sr Pb δ18O PO4‰ δ18O DW‰ Sample Age Tooth (ppm) 87Sr/86Sr (ppm) (SMOW) (Levinson) δ13C‰ δ15N‰ WEY08 SK3704 A URM2 70.4 0.71156 0.11 15.2 -12.2 -20.3 13.4 WEY08 SK3706 A ULM2 84.5 0.71032 0.17 15.9 -10.7 -20.4 10.4 WEY08 SK3707 YA LLM2 82.2 0.71306 0.13 15.1 -12.3 -19.8 13.1 WEY08 SK3710 A URM2 73.5 0.71060 0.09 16.6 -9.1 -21.0 11.7 WEY08 SK3711 A LLM2 95.2 0.71377 0.11 13.7 -15.5 -20.8 10.3 WEY08 SK3720 A LRM2 117.0 0.71294 0.09 15.6 -11.4 -20.8 12.6 WEY08 SK3724 YA LLM2 58.0 0.72051 0.15 15.8 -11.0 -21.1 12.4 WEY08 SK3730 YA? ULM2 97.6 0.71013 0.26 16.1 -10.2 -20.6 11.3 WEY08 SK3739 YA LLM2 61.2 0.71089 0.36 15.4 -11.6 -21.1 12.0 WEY08 SK3744 A LRM2 84.6 0.71072 0.10 15.8 -10.9 -19.9 13.8 Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 5 values is sensitive to the equation used and varies between drinking-water (δ18ODW) ranges of -15.5‰ and -9.2‰ using a modified Levinson equation (Chenery et al. 2010) and -12.6 ‰ to -8.2‰ using equation 6 from Daux et al. (2008), where δ18Ow = 1.54 x δ18Op - 33.72. When using the latter equation, some of these individuals fall within the more depleted range of British values. The calculated δ18ODW values for the group as a whole are low compared to those expected for the UK (-5‰ to -9‰; Darling et al. 2003) and are compatible with colder regions in Northern Europe such as Norway, Sweden, Finland, and Russia as well as parts of the Alps (Fig. 3). The oxygen isotope composition of eight of the individuals are between +15.1‰ SMOW and +16.1‰ SMOW (δ18ODW =-12.3‰ to -10.3‰) with an outlier (Wey08-SK3710) at 16.6‰ SMOW (δ18ODW =-9.2‰ SMOW) and an extreme outlier (Wey08-SK3711) at +13.7‰ SMOW (δ18ODW=-15.5‰ SMOW). This last individual has the lowest δ18O tooth enamel value yet found in Britain. Individual Wey08-SK3710 has the highest δ18O value, which would restrict his origins within Scandinavia to southern areas of Norway and Sweden, the Kattegat coast of Denmark, and southern Baltic countries, but these values are also consistent with large areas of central Europe. The origin of individual Wey08-SK3711, with the lowest δ18O value, is compatible with areas above the Arctic Circle, or Central Russia. Strontium isotopes Strontium isotope data for each tooth is presented in Table 1 and Figure 2. There is a wide range of values (0.71013 to 0.72051), which points to a diversity of origins for these individuals and confirms that none of them are “local” in the sense of having been raised in southern England (within the range 0.708–0.710; Evans et al. 2010). The highest 87Sr/76Sr value of 0.72051 (Wey08-SK3724) is very rare in the UK (Evans et al. 2010), but is compatible with the Precambrian geological terrains in Norway and Sweden. The strontium isotope composition of the other individuals does not exclude them from having been raised in Britain, but such values can equally be found in Scandinavia and the continent (Evans et al. 2010, Voerkelius et al. 2010). Norway and Sweden are composed of old rocks of Palaeozoic and Precambrian age. There is limited strontium biosphere data available from this area. High values (>0.72) are recorded for animals Figure 2. Plot of strontium and oxygen isotope data for Ridgeway Pit individuals, showing the locally expected 87Sr/86Sr range and UK range for d18O in UK drinking water. Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 6 into two phases: 1) the Neolithic to Iron Age when the only exposure is either natural or minimal, and 2) the last two millennia where lead became a pollutant resulting in bio-available exposure as soluble lead compounds. By the 8th–11th centuries AD, the median lead concentration in tooth enamel in Britain was 1.93 ppm (Montgomery et al. 2010). The very low level of lead recorded in this study indicates that the men came from a society where lead was not bio-available to the extent that is was in Britain at the same time, and hence the lead concentration data would support an origin outside of Britain. Carbon and nitrogen isotopes Carbon and nitrogen isotope results for dentine from each individual can be found in Table 1. The δ13C values for this group ranges from -21.1‰ to -19.8‰ with a mean of -20.6 ± 0.5‰ (1σ), and δ15N values range from 10.3‰ to 13.8‰ with a mean of 12.16 ± 1.2‰ (1σ). These results can be compared to published data from British, Belgian, and Scandinavian populations (see Figs. 4, 5). Comparing our data to British populations (Fig. 4), we find that the Weymouth δ13C values fall within the range for British Iron Age to Anglo Saxon populations of -21.2‰ to -19.1‰, (mean = -23.2‰ ± 0.4‰, 1σ, n = 192; Jay and Richards 2006, Muldner and Richards 2007, Privat et al. 2007, Richards et al. 1998), which have been intrepreted as being primarily terrestrial-based diets. However the majority of the Weymouth population have significantly higher and lake waters in Sweden by Aberg et al. (1995). Samples from 45 rivers plot largely between 0.72 and 0.74 from Sweden and Finland (Aberg and Wickman 1987). Human tooth-enamel data from southern Sweden records a range between 0.7104 in coastal Sweden to 0.7295 in more inland areas (Sjögren et al. 2009), which is a close match for the range of values found in the Weymouth group and suggests that the lower values may indicate an origin near the coast. Such lowering of biosphere values in coastal regions has been demonstrated by Evans et al. (2010). The geology of Denmark is very different. It comprises largely young, Cainozoic sediments which give biosphere values of 0.7096 ± 0.0015 (2σ) for most of the country (Frei and Frei 2011). Hence, the Scandinavian countries of Denmark, Norway, Sweden, and Finland are consistent with the range of Sr isotope values seen in these samples. The values over 0.711 are most likely to be from the Norway, Sweden, and Finland, whereas the values below 0.711 are much more common in Denmark and coastal areas. Lead concentrations in tooth enamel. The lead concentrations recorded in these 10 tooth-enamel samples are all below 0.4 ppm, and many are below 0.2 ppm (Table 1). Such low values correspond to values from “Prehistoric” individuals in the UK (Montgomery et al. 2010). In Britain, the changes in lead concentration in tooth enamel are related to exposure to lead sources and can be split Figure 3. Isotope map of Scandinavia compiled from IAEA/WMO (2006). IDW long-term annual average precipitation d18O map. Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 7 Figure 4. A comparison of carbon and nitrogen isotope composition of the Ridgeway Pit individuals with UK data. Data taken from: 1) Iron Age, Wetwang, Yorkshire (Jay and Richards 2006); 2) Iron Age, Poundbury, Dorset, UK (Richards et al. 1998); 3) Anglo-Saxon (individuals greater than 4 years of age), Berinsfield, Oxfordshire, UK (Privat et al. 2007); 4) Anglian (late 8th to early 9th century), York, UK (Müldner and Richards 2007); 5) Medieval, Belgium (Polet and Katzenberg 2003); 6) late 13th century, Warrington, Cheshire (Müldner and Richards 2005); 7) late 12th to late 13th century, Fishergare, York, (Müldner and Richards 2007); 8) 10th –16th century, Warram Percy, Yorkshire, UK (Fuller et al. 2003); 9) 12th –15th century, Brompton Bridge, North Yorkshire, UK(Müldner and Richards 2005); and 10) Weymouth pit burial, this study. Richards 2007), and 12th–15th-century Brompton Bridge, North Yorkshire, UK (Müldner and Richards 2005), where diets contained marine and riverine fish components. δ15N values than these groups and are more similar to those found in late-13th-century Warrington, Cheshire (Müldner and Richards 2005), late-12th- to late-13th-century Fishergare, York, (Müldner and Figure 5. A comparison of carbon and nitrogen isotope composition of the Ridgeway Pit individuals with Scandinavia. Data taken from: 1) Rossberga, Sweden, Stone Age, Inland (Liden 1995); 2, Resmo, Sweden, Stone Age, Coastal (Liden 1995); 3) Denmark Neolithic Inland (Fischer et al. 2007); 4 Denmark Neolithic Coastal (Fischer et al. 2007); 5) Bjarby, 1st–2nd century Roman Period, Sweden, M2 data only (Eriksson et al. 2008); 6) Bjorned, N. Sweden, Christian,10th – 13th century (Linderholm et al. 2008b); 7) Sigtuna, Sweden, Christian, Phase, A.D. 900–1100 (Kjellstrom et al. 2009); 8) Birka, Sweden, Viking Period, 9th -10th century; 6 (Linderholm et al. 2008a); and 9) Weymouth pit burial, this study. Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 8 In contrast, the Weymouth data lies within the range for the Scandinavian data (Fig. 5) and in particular is similar to data from Bjorned, N. Sweden, Christian, 10th–13th century (Linderholm et al. 2008b) and Birka, Sweden, Viking Period, 9th–10th century (Linderholm et al. 2008a). The combined δ13C data for Bjorned and Birka range from -20.2‰ to -19.0‰ (mean = -20.3 ± 0.7‰, 1σ, n = 70) and for δ15N from 12.5‰ to 16.5‰. These results suggests that the Weymouth individuals are likely to have had a diet similar to that of the Bjorned and Birka communities, which has been interpreted as being terrestrial with a significant freshwater fish component. Discussion: Where could this group of men have originated? This group of individuals show a diversity of origins, with two very significant outliers in terms of oxygen isotope composition (WEY08 SK3711) and strontium isotope composition (WEY08 SK3724). At the same time, however, the oxygen isotope data provides strong evidence that the ten men whose teeth have been analyzed, and by inference the rest of the group of 51, were all raised in a climate that was considerably colder than that of Britain. The majority are consistent with an origin in much of central Norway, Sweden, Finland, and parts of western Russia. The man with the most depleted oxygen isotope signature is more likely to have had a childhood origin in arctic Scandinavia or arctic/central Russia. The lead concentrations indicate that these men had lower levels of lead exposure than typical for inhabitants of 8th–11th-century Britain. The carbon and nitrogen data reflect a Scandinavian diet with a higher nitrogen isotope value than the equivalent British diet from the same period. The strontium isotopes are consistent with a Scandinavia origin. The value of 0.72 (WEY08 SK3724) is entirely consistent with a childhood origin on old Precambrian cratonic rocks that underlie most of Norway, Sweden, and Finland in the form of the Baltic shield. The values near 0.713 (three individuals) are consistent with areas of Palaeozoic rocks and the values of 0.710 to 0.711 are more typical of either areas of younger rocks or coastal areas (Evans et al. 2010). The period of 970 and 1025 AD to which these executed men are dated saw the onset of regular Viking attacks on England. “A.D. 982. In this year came up in Dorsetshire three ships of the pirates, and plundered in Portland. The same year London was burned” (from Ingram’s [1823] translation of “The Anglo-Saxon Chronicle”). Ethelred II started paying Danegeld to try to minimize the attacks on London during the period A.D. 991–994, and in 1009, Olaf Harrisen destroyed London Bridge and helped the Danes conquer England. Canute gained control of England in A.D. 1016 and was crowned King of England in A.D. 1018. It is tempting to consider that an event such as a mass execution might be recorded historically, and the Anglo Saxon Chronicles do provide descriptions of such events that might be appropriate. The St. Brices Day massacre occurred during the appropriate time period, but this event involved the local population turning upon resident Viking settlers and hence the massacre victims might be expected to be of mixed age and sex and some would likely have been born in England. One event that could account for the execution of 51 men is described below from the Anglo Saxon chronicles for AD 992: “A.D. 992. This year the blessed Archbishop Oswald departed this life, and sought a heavenly one; and in the same year died Alderman Ethelwin. Then the king and all his council resolved, that all the ships that were of any account should be gathered together at London; and the king committed the lead of the land-force to Alderman Elfric, and Earl Thorod, and Bishop Elfstan, and Bishop Escwy; that they should try if they could anywhere without entrap the enemy. Then sent Alderman Elfric, and gave warning to the enemy; and on the night preceding the day of battle he sculked away from the army, to his great disgrace. The enemy then escaped; except the crew of one ship, who were slain on the spot. Then met the enemy the ships from East-Anglia, and from London; and there a great slaughter was made, and they took the ship in which was the alderman, all armed and rigged.” (Ingram 1823) The Anglo Saxon chronicle also refers to frequent raids on Exmouth and Wiltshire between 1001 and 1003; however, there are no references to Weymouth or specific mention of locals defeating the raiding parties. The slaughter of a ship’s crew would fit well with the fact that this executed group was all male and mostly in their twenties suggesting some type of warring or raiding group of men. Fifty one men would provide a realistic-sized crew for a Viking longship and conform to a model of 25 pairs of oarsmen and one cox from one of the larger boat designs (Hale 1998). Whether or not we shall ever make a positive historical identification of this event remains unknown. What we can take from this discovery is that the massacre site contains the largest group of first-generation Scandinavian individuals to be found within the archaeological record of Britain to date. Journal of the North Atlantic C.A. Chenery, J.A. Evans, D. Score, A. Boyle, and S.R. Chenery 2014 Special Volume X 9 Dansgaard, W. 1964. Stable isotopes in precipitation. Tellus 16:171–177. Darling, W.C., A.H. Bath, and J.C.Talbot. 2003. The O & H stable isotopic composition of fresh waters in the British Isles: 2, Surface waters and groundwater. Hydrology and Earth System Sciences 7:183-195. Daux, V., C. Lecuyer, M. A. Heran, R. Amiot, L. Simon, F. Fourel, F. Martineau, N. Lynnerup, H. Reychler, and G. 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International Journal of Osteoarchaeology 13:20–28. International Atomic Energy Agency (IAEA). 2006. Global network of isotope precipitation. Available online at http://www-naweb.iaea.org/napc/ih/IHS_resources_ gnip.html. Accessed 9 October 2014. Ingram, Rev. J. 1823. Anglo Saxon Chronicles. London, 1823. Published in “The Anglo-Saxon Chronicle”, Everyman Press, London, UK, 1912. Available on line at http://omacl.org/Anglo/part3.html. Accessed 9 October 2014. Jay, M., and M.P. Richards. 2006. Diet in the iron age cemetery population at Wetwang Slack, East Yorkshire, UK: Carbon and nitrogen stable isotope evidence. Journal of Archaeological Science 33:653–662. Conclusions 1. The oxygen isotope composition of the tooth enamel of these individuals is beyond the range of UK values and consistent with an origin in a colder climate. 2. The calculated drinking water oxygen isotope composition is consistent with an origin in Scandinavian countries. 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