Stable isotope analysis of a medieval skeletal sample indicative of systemic disease from Sigtuna Sweden Anna Linderholm a,1 , Anna Kjellström b, * a Archaeological Research Laboratory, Department of Archaeology and Classical Studies, Stockholm University,106 91, Stockholm, Sweden b Osteoarchaeological Research Laboratory, Department of Archaeology and Classical Studies, Stockholm University, Lilla Frescativägen 7, SE-106 91, Stockholm, Sweden article info Article history: Received 1 July 2010 Received in revised form 22 November 2010 Accepted 25 November 2010 Keywords: Systemic disease Leprosy Tuberculosis Social classes Diet Stable isotopes Carbon Nitrogen Sulphur abstract In Sigtuna, Sweden, several medieval cemeteries have been excavated, from which approximately 800 skeletons have been excavated and analysed. Archaeological finds and anthropological analyses have exposed social differences between the cemeteries. Stable isotope analyses have shown that the inhabitants of the town consumed a mixed diet. Significant differences in dietary patterns between the cemeteries may be related to social stratification. In the outskirts of a churchyard excavated in 2006, bone changes showing systemic inflammatory disease indicative of leprosy were observed in six individuals. The burial location suggests that the affected belonged to a lower social stratum. Bone samples were taken from these six individuals, 19 other human skeletons and five animals from the same cemetery for analysis of the stable isotope composition of carbon (C), nitrogen (N) and sulphur (S). The results showed no significant differences in d 13 C and d 15 N values between the groups, i.e. the seemingly healthy humans and the humans affected by severe inflammatory disease appear to have had similar diets. Nor was a significant difference observed in d 34 S data between the six affected individuals and the rest of the sample, implying that no difference in origins could be observed between the two groups studied. However, a comparison between the present study and the previous analysis resulted in significant differences in carbon values. Based on the results obtained in this investigation it is suggested that if a dietary difference existed between people in the outskirts of a cemetery (for example those suffering from leprosy) and people buried in higher ranked regions, it was not a difference in food source but rather in other parameters. Instead dietary differences and possibly social variations are demonstrated between cemeteries. The results from the present study highlight the hierarchical arrangements of social classes in the early medieval society. Ó 2010 Elsevier Ltd. All rights reserved. 1. Introduction Individuals with leprosy have been documented in Sigtuna. In a grave excavated in 1995 associated with the church known as “Church 1” (Kjellström, 2005), an affected individual was identified. The grave was located in the periphery of the churchyard. The placement of the graves is in line with coeval Scandinavian burial regulations (for example the Norwegian law Eidsivatingslagen), which assigned the areas most distant from the church to the poor or outcasts (Gejvall, 1969: Daniell, 1997). A similar location for people with skeletal changes of leprosy, showing their low social position in society, has been documented in medieval Lund, in the south of Sweden (Arcini, 1999). The present study considers the diet and origins of six individ- uals also discovered in the outskirts of a medieval churchyard in Sigtuna. Skeletal changes indicate that the group had suffered from systemic disease. Their burial location implies that these individ- uals also belonged to a low social stratum. Previous studies have shown that dietary differences, most likely related to social hier- archy, already existed between groups during the initial phase of the town’s establishment (Kjellström et al., 2009). Although knowledge of the current church and churchyard is low it was most likely not a formal nursing institution. (A hospital was first estab- lished in Sigtuna in A.D. 1287, around the time of the abandonment * Corresponding author. Tel.: þ46 8 161287; fax: þ46 8 164476. E-mail address: anna.kjellstrom@ofl.su.se (A. Kjellström). 1 Present address: Department of Archaeology, Durham University, South Road, Durham DH1 3LE, United Kingdom. Contents lists available at ScienceDirect Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas 0305-4403/$ e see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.jas.2010.11.022 Journal of Archaeological Science 38 (2011) 925e933