Wohlstand durch Wolle: isotopische Herkunftsbestimmung von Schafwolletextilien aus mittelalterlichen Städten in Nordeuropa
Mittelalterliche Geschichte
Tierzucht, Tierernährung, Tierhaltung
Zusammenfassung der Projektergebnisse
Historical documents indicate that wool textile industry in the Middle Ages (9th-15th centuries) was large and profitable: making and selling wool textiles was important both economically and socially in all parts of Europe. Many different types of cloth were made, and many were worth enough to be traded long distances. However these cloths are rarely described in enough technical detail to allow them to be identified from among the hundreds of fragments of wool textiles recovered from archaeological excavations in medieval towns in northern Europe. These objects represent the work and belongings of a cross-section of medieval urban societies, including people and places which are underrepresented in contemporary documents. Understanding where these objects originated is an important addition to the information on textile trade and consumption derived from historical sources, which typically record only the first sale of new cloths, to relatively rich consumers or middlemen. This project analysed the carbon (δ13C), nitrogen (δ15N) and hydrogen (δ2H) isotopic composition of textiles from seven medieval urban assemblages around the Baltic and North Seas: Dublin (IE, 8th-10th centuries), Haithabu and Schleswig (DE, 3 assemblages, 9th-15th centuries), Tønsberg (NO, 12th-14th centuries), Tartu (EE, 13th-15th centuries) and Turku (FI, 14th-15th centuries). Ecological and food studies have shown that sheep wool isotopic composition depends on where a sheep lived, because of variation in temperature, humidity, plant types in pasture, soil type, etc., and also on how the sheep was farmed, e.g. given different types of fodder, moved between different types of pasture. These values are not greatly altered by burial, so these analyses can therefore be used to identify the region of origin of an archaeological wool textile. The data in this study established that patterns of isotopic variation in medieval caprine bone collagen from the region are broadly similar to those in modern sheep wool, indicating predominantly local supplies of sheep livestock to each site. One significant difference was the presence of grazing on salt-marshes or –meadows, identified by relatively elevated δ13C, δ15N and δ2H values, which made a minor contribution to the bone assemblages at Haithabu/Schleswig from the 10th to the 15th centuries. There was an unexpectedly wide range of δ15N and δ2H at Tønsberg, which is difficult to interpret given the current paucity of archaeological caprine isotope data from the region. Non-local textiles were identified at all sites by comparison to the local bone collagen values, and allowing for the sort of isotopic variation in wool expected in a single modern flock. The minimum proportion of isotopically non-local textiles ranged from 17% at Haithabu to 73% in Tartu. In Tartu and at Turku, most textiles with outlying isotope values had composition consistent with wool from the North Sea region (DE, GB, Benelux), in line with historical documents indicating the importance of the trade in wool cloths from this region by the Hanse, in parallel with the consumption of ceramics but in contrast to the use of local sheep for food. Textiles with isotopic values consistent with an origin in the Baltic region (EE, FI, SE) were identified in Tønsberg and Haithabu/Schleswig, indicating that some wool objects (and surprisingly, some felt and raw fibre) travelled in the opposite direction. Textiles with isotope values consistent with an origin in the North Atlantic (IS, northern/upland NO) were identified in 10th century Dublin (IE) and at Tønsberg. The results demonstrate the effectiveness of isotopic analysis to investigate the movement of wool textiles in medieval Northern Europe. The results variously confirm, refine and/or complement the information in historical documents, and from modern artefactual analyses of archaeological textile fragments, to understand mobility of objects and people. This data will be published as a series of detailed case studies in peer-reviewed journals, focusing on the integration of artefactual and scientific data in archaeology.
