The original work that declared only men raided assumed that anyone buried with a sword was a man. Actually looking at the bones reveals that the sex ratio was likely even.
Invasion of the Viking women unearthed - Science Fair - USATODAY.com
Vikings famously invaded Eastern England around 900 A.D., notes Shane McLeod of the Centre for Medieval and Early Modern Studies at the University of Western Australia in the Early Medieval Europe journal, starting with two army invasions in the 800's, recounted in the Anglo-Saxon Chronicles. The Viking invaders founded their own medieval kingdom, 'the Danelaw', in Eastern England.
"There is some archaeological evidence for early Norse female settlement, most obviously oval brooches, but this evidence is minimal. The more difficult to date evidence of place names, personal names, and DNA samples derived from the modern population suggests that Norse women did migrate to England at some stage, but probably in far fewer numbers than Norse men," begins the study.
However, McLeod notes that recently, burials of female Norse immigrants have started to turn up in Eastern England. "An increase in the number of finds of Norse-style jewellery in the last two decades has led some scholars to suggest a larger number of female settlers. Indeed, it has been noted that there are more Norse female dress items than those worn by men," says the study.
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The bones were sorted for telltale osteological signs of which gender they belonged to, rather than assuming that burial with a sword or knife denoted a male burial.