Archaeological site Sowinki no. 23A is located in Greater Poland province (województwo wielkopolskie), about 35 km south-east of Poznań. It is situated on a vast, sandy headland at the edge of the Warta river valley fluvial terrace. The entire site was excavated in the years 1989–1991, in connection with a planned construction of a water treatment plant for the city of Poznań. Sowinki site no. 23A is a multicultural site (Krzyszowski, 1992, 1995, 1997, 2014), with the remains of occupation ranging chronologically from the Mesolithic to the Medieval period (Fig. 1). The examined area provides a record of the history of Greater Poland (Poznań) region tracing back to about seven and a half thousand years ago.
The above necropolis is the most important discovery at the site of Sowinki due to the scope of excavations allowing for the exploration of its entire area, a long period of use, dating — which is worth emphasizing — to the beginnings of the Poland’s state, as well as the scarcity of other skeletal cemeteries from the time of the early Piasts’ dynasty. Also, findings concerning the site provide a valuable background for the study on the emergence of the early medieval culture of elites. Notably, some of the artefacts unearthed at Sowinki have analogies with Scandinavian finds of the Middle and Late Viking periods.
Sowinki site no. 23A is a multicultural site. The excavations covered an area of about 1.5 ha and revealed altogether 580 features representing 7 chronological-cultural horizons, which include:
a campsite dating to the Late Mesolithic period (about 6–5 thousand years BC) — the remains of the “younger” settlement involved over a dozen flint items, including microlithic cores, truncated blades, scrapers, as well as blades and flakes (Fig. 2);
a settlement site attributed to the communities of the Funnel Beaker culture dating to the Neolithic period (so called Wiórecka phase, about 3.5–3 thousand years BC) — distinguished on the basis of several dozen pottery fragments of, among others, the Funnel Beaker culture. No features were recorded at this site; however, they had probably been destroyed by more numerous “younger” remains of the communities of the Lusatian culture, Pomeranian culture and early medieval occupation; a settlement attributed to the communities of the Lusatian culture dating to the Hallstatt period HaCD (about 700–450 BC) — the finds included 383 features and several hundred pottery fragments, testifying the existence of a vast settlement with several dwellings, outbuildings and production facilities; nearly all the boundaries of this settlement were registered during the research, except for its north-eastern periphery; a cremation cemetery attributed to the communities of the Pomeranian culture dating to the Roman Influence period (about 400–300 BC) — the research revealed 43 burials of this cultural unit (heavily destroyed) comprising altogether the remains of 55 people. They were deposited in a central part of the site located on an elevation. The most outstanding of various grave types recorded at this cemetery were two cist graves; one of them, intact, comprised stone constructions containing 13 cinerary urns with human remains; possibly this was a family burial (Fig. 2); a settlement site attributed to the Przeworsk culture dating to the Pre-Roman period LtC (about 200–100 BC) — registered finds comprised two features (pits) and several pottery fragments, which belonged to the south-western periphery of a settlement of the same cultural unit, situated at a neighbouring site of Sowinki 23B; a settlement trace dating to the Late Medieval period (14th–15th cent.AD) — a single feature (pit) containing an iron artefact and several wheel-thrown pottery fragments;
Detailed analyses and 14C measurement were provided for samples from the skeletal cemetery dating to the Early Medieval period (
Previously, chronological frameworks of the Sowinki site were determined on the basis of relative chronology, according to stratigraphy of sediments, examination of metal finds, pottery and flint objects. These studies revealed that the cemetery at Sowinki had been used in the period between the second half of the 10th cent. and the first half of the 12th cent. The above archaeological findings have been verified through radiocarbon dating of the material collected from several graves (
Samples of wood and bones representing various periods were collected from different features, including mostly cellar pits, refuse pits and grave pits. The deposition depth of the analysed samples did not exceed 100 cm below ground level. Radiocarbon dating was carried out so far on 8 samples, all of which were acquired from grave pits of the skeletal cemetery dating to the Early Medieval period (
Samples from Sowinki, location and features characteristics.Sample name Material Feature no. Feature type Archaeological artefacts from feature SOWI/ob70/1/1989 Birch ( 70 skeletal burial 38 artefacts: 3 iron knives, wooden bucket, 2 whetstones, belt buckle, iron scissors, folding weighing machine, 18 weights, 6 fishing hooks, 2 awls SOWI/ob61/1/1989 Human bone ( 61 skeletal burial 1 iron knife, 1 pottery vessel S 23A L4/2014 Human bone ( 151 skeletal burial 8 artefacts: 2 iron knives, ornamented wooden bucket, whetstone, spear head, 2 spurs, spur buckle, awl Sowinki 23A Human bone ( 148 skeletal burial 30 artefacts: 2 iron knives, wooden bucket, whetstone, arabic silver dirham (from the years 950-976), silver ring, coffin fittings Sowinki 23A/78 Human bone ( 78 skeletal burial - Sowinki, 23A gr 57 Human bone ( 57 skeletal burial 1 iron knife, SOWI/ob367/1/1989 Human bone ( 367 skeletal burial 1 iron knife, 2 temple rings Sowinki, 23A gr 441 Human bone ( 441 skeletal burial -
Dating of wood fragment and bones was carried out in Poznan Radiocarbon Laboratory. Charcoal samples were prepared by the AAA method (Acid – Alkali – Acid) to remove any impurities, first carbonate (treated with a hydrochloric acid solution), than the organic pollutants, humic acids (treated with a solution of sodium hydroxide) and at the end to remove an atmospheric carbon (CO2), which could be absorbed by the samples during preparation (treated with hydrochloric acid again). Each time, the samples were bathed in deionised water to restore the neutral pH. Next step after the initial preparation involves combustion of the samples, processing of the CO2 to obtain a graphite and compression in a special holder to form a disc ready for AMS measurement.
In case of bones, collagen extraction procedure was applied (Longin, 1971; Stafford
Results of 14C dating; M — material, W — wood, N, C — nitrogen and carbon percentage, given for bone samples; Lab code: Poz — sample dated with the AMS technique in the Poznan Radiocarbon Laboratory; calibration with OxCal v4.2.4 (Bronk Ramsey et al., 2013) and IntCal13 atmospheric curve (Reimer et al., 2013).14C Age Cal. Age Cal. Age Sample Name M Lab. no. (BP) (68.2% conf. intervals) (95.4% conf. intervals) (calAD) (calAD) SOWI/ob70/1/1989 W Poz-43127 1145 ± 30 775(4.5%)790 775(95.4%)975 870(63.7%)970 SOWI/ob61/1/1989 1.9% N Poz-43126 1060 ± 30 965(68.2%)1020 895(14.4%)925 6.2% C 940(81.0%)1025 1.5% N 899(24.2%)924 S 23A L4/2014 4.9% C Poz-64262 1090 ± 30 945(44.0%)990 892(95.4%)1014 8.4% coll 1.4% N 895(27.8%)925 Sowinki 23A 4.8% C Poz-72015 1100 ± 30 940(40.4%)985 885(95.4%)1015 9.0% coll 1.4% N 1025(20.5%)1050 Sowinki 23A/78 3.8% C Poz-72789 955 ± 30 1080(36.0%)1125 1020(95.4%)1155 12% coll 1135(11.8%)1155 0.8% N 1015(39.6%)1050 990(51.3%)1060 Sowinki. 23A gr 57 3.1% C Poz-76789 985 ± 30 1090(23.7%)1125 1075(44.1 %)1155 8.7% coll 1140(5.0%)1150 2.1% N 1045(33.0%)1095 SOWI/ob367/1/1989 6.5% C Poz-43128 900 ± 30 1120(11.8%)1140 1035(95.4%)1210 1145(23.5%)1185 1.3% N 1030(15.4%)1055 Sowinki. 23A gr 441 3.7% C Poz-76791 945 ± 30 1080(52.8%)1155 1025(95.4%)1160 1.8% coll
Bone, wood and charcoal samples provided eight dates, which confirmed previous findings concerning different cultures registered in the studied area, and, additionally, they have helped to clarify the chronology of the early medieval cemetery. The demonstrated results are the first isotopic measurements taken for the site of Sowinki. The obtained data have allowed for defining two chronological phases of the early medieval cemetery (
Radiocarbon dating results of samples from Sowinki, together with probability for 68 and 95% are presented in
Radiocarbon dating results and some of the finds unearthed at Sowinki reveal the direction of cultural links between the early medieval Greater Poland and other regions. They include a merchant balance scales with a set of weights (from grave no. 70), identified as an import from the western European-Scandinavian cultural circle (
Comparing the cemetery at Sowinki with other early medieval burial grounds containing elite chamber graves with “Rus-Scandinavian” elements in equipment one can clearly identify chronological correlation between them (
On the basis of the historical material it has been determined that the cemetery in Sowinki was used from the second half of the 10th century up to the first half of the 12th century. The findings basing on the relative chronology have been verified through radiocarbon dating performed in Poznan Radiocarbon Laboratory for samples taken from eight graves, and through the dating of silver coins (Krzyszowski and Suchodolski, in press). The outcome data allowed for distinction of two chronological phases of the cemetery (
An important matter was to obtain 14C dates especially from two graves: number 148 and 151 (from phase I), (Krzyszowski and Błaszczyk, 2016). They are the scarce examples of early medieval chamber graves on Polish lands, where the buried ones were probably young men equipped with rich grave accessories. Indubitably they belong to the one of the oldest, perhaps even founding burials at the cemetery at Sowinki. Both graves were created in the times of the so called first Piasts’ Monarchy, most probably during the reign of Bolesław Chrobry or even Mieszko I, which were the times of the intensive Christianisation, forming of grand social differentiation and development of the early-state structures in the Polish lands. The dates received from the radiocarbon measurements confirmed the previous findings in that scope, based upon traditional analysis of the archaeological materials, including coins (Krzyszowski, 1992, 1995, 1997, 2014; Krzyszowski i Suchodolski, in press). The cemetery at Sowinki with well-documented oldest chamber burials is compatible with (and yet probably the oldest of) other early-medieval cemeteries. Elite chamber graves with Rus-Scandinavian elements in their equipment have been documented also in: Kałdus on the Chełmno lands, Pień, Bodzia and Ciepło on the Kuyavian-Pomeranian lands as well as in Dziekanowice in Greater Poland. The above mentioned burials from Sowinki refer to a greater idea of so called chamber graves recorded in early medieval burial rites in Central and Eastern Europe and in Scandinavia, mostly in Sweden and Denmark (Janowski, 2015). Such graves were reserved for the members of contemporary elites, including people involved in trans-regional trade. The cemetery at Sowinki is one of the burial grounds, which possibly served as a resting place for representatives of the people of Scandinavian origin who settled in the Piasts’ state with the consent of the local authority.