Arctic Norway is an important region for human-environmental research because early settlements were at the northern limits for agriculture and had mixed agricultural and maritime economies that were susceptible to climate and sea level changes. In the Lofoten Islands, settlements developed from small pioneering agricultural outposts to prominent nodes of power and trade under Viking chiefdoms during the Iron Age (c. 500 BCE - 1100 CE). The collapse of these chiefdoms occurred during the late Iron Age at which time these societies were associated with westward migrations to other North Atlantic islands, which helped spread agricultural, maritime, and cultural knowledge that was subsequently adapted to suit these new environments. The Iron Age in Arctic Norway therefore marks an important period in the human history of the North Atlantic to assess the influence of natural environmental changes within an informed cultural framework. By examining archaeological records from the region and generating new paleoenvironmental data using lake sediments, we have been able to document the relationship between landscape changes, sea-level variations, and the human history of the islands over the last few thousand years. We compiled Iron Age archaeological data to show the geographical scale and timing of early settlement activity. We found the highest concentration of sites on the island Vestvagøy, with an increase in both the spatial extent and number of site types from the Early to the Late Iron Age. Most sites were found near two prominent chiefdoms on the island at Leknes and Borg. Paleoenvironmental records developed from adjacent areas on Vestvagøy compliment these archaeological data. We found initial evidence for land clearance associated with pioneering agricultural settlements as early as 5,000 years ago, with much more significant changes starting at the onset of the Early Iron Age, c. 2400 years ago. We interpret these human-driven landscape changes from sedimentary pollen data, which indicate changes in forest composition and the introduction of non-native vegetation, and from indicators of fire activity, including charcoal and polycyclic aromatic hydrocarbon biomarkers. We also analyzed fecal biomarkers, 5b-stanols, to further characterize human land use. We were able to find clear evidence of these biomarkers in cultural horizons recovered from an Iron Age longhouse and boathouse structures showing that they are produced and preserved on the landscape and do have differences attributed to archeological site type. However, in the lake sediment records, we were only able to find significant concentrations of these biomarkers over the last few centuries showing that there may be transportation, dilution, or other processes impacting their preservation in lakes that requires further investigation. In addition to examining the nature and timing of human-landscape changes, we investigated the rate and pattern of sea-level lowering surrounding the Iron Age. Analyzing sediment records from lakes uplifted from below sea-level over the last few thousand years (isolation basins), we were able to improve constraints on the regional sea-level history. We demonstrated how relative sea-level variations influenced the location and preservation of coastal settlement locations and harbors from the early Stone Age through historical intervals. In particular, we were able to show how sea-level change impacted the accessibility of a Viking Age harbor, which likely contributed to the eventual decline in its usefulness, and as a location of cultural and economic importance. Overall, our datasets improve our understanding of the ways in which humans have influenced, or been influenced by, environmental change. In addition, this work advances knowledge of the application of sedimentary indicators of past human landscape activities. This NSF project provided training for one postdoctoral scholar, two graduate students, and eight undergraduate students, many of whom are now pursuing careers in research, environmental industries, and STEM education.

Last Modified: 10/12/2023
Modified by: Nicholas L Balascio