29 (466)

52 The Viking Age in Denmark

We have already mentioned the expansion of grasses, and it is not surprising to find ribworth plantain indicating cattle grazing as a fcature accompanying the development of the early Iron Age (500 B.C. to 400 A.D.). In the Viking Age species of grass were again expanding, along with cereals, after the forest regeneration phase; now, however, the ribworth plantain was markedly decreasing. This shows that Viking Age farming put much less emphasis on animal protein than earlier periods. The intensive growing of plant protein led to a higher nutritional output. It is hard to conceive of this as anything but a response to population growth. Furthermore, forest grazing may have becomc morę important, but if so it suggests the stress placed on cereal production. Finaily, the size of the animals, except for horses, was decreasing in the Viking Age, probably as a result of poorer nutrition.¹⁴ This development was not isolated, for to the south of Denmark the growing of cereals expanded during the last quarter ofthe first millennium A.D.¹⁵

From the Viking Age we have several examples of the use of a heavier plough - the mouldboard wheeled plough - which tumed the ground when working, and in the Middle Ages became at least a partial substitute for the older ‘ard’-types, which only madę furrows in the ground.¹⁶ One example of its use from Sjaelland stems perhaps from as early as the seventh or eighth century A.D.,¹⁷ but south of Denmark we have even earlier indications of the mouldboard plough.^1M

The human influence factor in the pollen diagrams of Southern and central Scandinavia has been tentatively described by an interpretation of the pollen curves of trees and of light-demanding plants (Fig. 12).¹⁹ Four early stages of growing human impact are developed, lying parallel to each other in the different arcas with little, or no, time lag in between. That some temporal distinctions do exist is probably due to the population growth, conditioning the impact. The first stage is the

Figurę 12 Diagrams of the human influence on the vegetation (shaded). Dates in uncalibrated C¹⁴-years. (After Berglund)

Neolithic landnam, which, for example, is earlier on the Danish islands than in, say, Southern Norway. The second stage is the grcat influence from the beginning of the so-called Middle Neolithic period (3000 B.C.) onwards. The third corresponds to our expansion during the mildcr climatic conditions around the tum of the first millennium B.C., and the fourth to the latest Iron and Viking Age growth, continuing to the early Middle Ages, and also very visible in the diagrams for areas south of Denmark. An additional, finał stage corresponds to the modem, post-medieval expansion.

The correlation between the major climatic optima and the periods of expansion of the open land for fields and pastures suggests that better harvests, in the first place, created a population growth which later caused inroads to be madę into the forested area. The reverse must have happened at the onset of poorer climatic conditions. However, the depression around 500 A.D. may have been felt so strongly in the densely settled and centrally organised country that it was decisi ve in enabling a larger part of the population to survive. This was perhaps achieved by the change in the subsistence strategy leading to the expansion of cornfields at the expense of pastures.

The third stage, or early Iron Age, seems to have culminated earlier on the sandy and morę rapidly leached west Jylland soils than in those areas further to the east and north in Scandinavia. This is in accordance with the settlement data. Moreover the expansion after the depression around 500 A.D. is slightly earlier in west Jylland than in the eastern parts of Denmark. We have already outlined the possible pressures on the east in the early Iron Age due to these circumstances. For the latter half of the first millennium A.D. the west may have served as an area of colonisation, partly through a renewed period of slash-and-burn agriculturc. Forest regeneration is certainly very pronounced. Southernmost Jylland, for instance, is strongly resettled,²⁰ and in 700, or shortly after, the first Danevirke walls were constructed at the border with the Saxons (Chapter 5 E).

It is elear that the entire Viking Age experienced a growth in population, but it is equally elear that this development started much earlier than the political evolution leading to the formation of the State of Denmark at the close of the tenth century. In the centuries at the tum of the first millennium B.C. the size of the open land was almost as large as at the beginning of the Viking Age, but owing to the wide-scale concentration on cattle-rearing the population was probably somewhat smaller. The early Iron Age did not see any social formation which we would term a State with the Viking Age in mind. In this perspective the population density and pressure on the re-sources must have played a role in the creation of the high degree of political control of the Viking period, though we are not able to connect the onset of population growth with a particular social development. Just as supercooled water may freeze at an accidental