The megaliths of Bohuslän in a south Scandinavian context

Sammanfattning: The transformation from a hunter/gatherer population to a farming society in southern Scandinavia is a process of only 300-400 years, primarily from around 4000 BC to around 3700 BC. Farming is then established in most of southern Scandinavia. In Denmark and Scania there is a continuous development of grave monuments starting from flat graves and peaking with very large passage graves. The primary steps are plank cists, changing to stone cists, followed by different versions of dolmens and then the passage grave. Another important construction is the early type of enclosure, used for special events at long intervals. In Bohuslän and Falbygden the initial types of graves and the enclosures are not present, or maybe not yet found. There are close to one hundred megaliths along the west coast of Sweden, with a high concentration to the islands Orust and Tjörn together with the area north of Orust. 29 megaliths are on Orust. There are in total 33 identified passage graves and fifty dolmens, a few are undefined. The architecture of dolmens and passage graves is principally the same all-over southern Scandinavia, but the appearance is quite different due to the local availability of stones. In Denmark and Scania, the megaliths are built of stones left by the ice age, mainly rounded stones. In Bohuslän the material is flat stones from the cliff sides, split by the ice age and in Falbygden the material is primarily sedimentary stone slabs. The essay discusses the relation between the megaliths in Bohuslän and the other areas, especially Jutland. It has been stated from the early archaeologists to the recent, that Bohuslän is related to Jutland, the so-called Kattegat connection. It is argued that the empirical evidence for a stronger relation between Bohuslän and Jutland compared to the other areas is weak. There are some artefacts and some architectural designs which may be influenced from Jutland, but it seems that the influence could have come from other areas as well. The view of the time sequence of dolmens and passage graves differ between Denmark and Sweden. In Denmark the archaeologists describe a sequence of dolmens followed by a sequence of passage graves, with an overlap of the later dolmens and the early passage graves. In Sweden the view is that dolmens and passage graves were built mostly during the same period, with the dolmens starting slightly earlier. This discrepancy is explored using the most reliable C14 data which has been presented for dolmens and passage graves in Denmark and Sweden. The data is limited and consequently the conclusions have uncertainties. A complication in analysing C14 data for the megalith period is that there is a plateau in the calibration curve during the most important period, giving an almost 300 years uncertainty. An analysis of the data shows that the dolmens are built during this plateau phase and some of them with a probability that it was before this period. No dolmen seems to be built after the plateau. For the passage graves it is the other way around. Passage graves are built during the plateau, some are built after and none before. It is argued that this implies that the dolmens in southern Scandinavia primarily are built before the passage graves with an undefined overlap in the plateau period.