Original Article
Male-biased operational sex ratios and the Viking phenomenon: an evolutionary anthropological perspective on Late Iron Age Scandinavian raiding

https://doi.org/10.1016/j.evolhumbehav.2016.10.013Get rights and content
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Abstract

In this paper, we use a combination of evolutionary theory, ethnographic data, written sources, and archaeological evidence to develop a new explanation for the origins of Viking raiding. Our argument focuses on the operational sex ratio, which is the ratio of males to females in a society who are ready to mate at a given time. We propose that a combination of two practices – polygyny and concubinage – and the increase in social inequality that occurred in Scandinavia during the Late Iron Age resulted in a male-biased operational sex ratio. This would have created a pool of unmarried men motivated to engage in risky behaviours that had the potential to increase their wealth and status, and therefore their probability of entering the marriage market. With high-status men looking to instigate expeditions to acquire plunder and develop their reputations as war leaders, raiding represented a mutually beneficial means of achieving social advancement and success.

Keywords

Vikings
Late Iron Age Scandinavia
Raiding
Polygyny
Concubinage
Operational sex ratio
Male-male competition

Cited by (0)

BR and MC are supported by the Social Sciences and Humanities Research Council of Canada through a Partnership Grant (895-2011-1009) awarded to the Cultural Evolution of Religion Research Consortium (www.ubc/hecc/cerc). MC is also supported by the Canada Research Chairs Program, the Canada Foundation for Innovation, the British Columbia Knowledge Development Fund, and Simon Fraser University. NP is supported by a Swedish Research Council grant for "The Viking Phenomenon" project (2015-00466).