[4] Nordvig challenges a common view that the lack of unambiguous references to volcanoes in textual sources means that they left little trace in Viking Age and medieval Icelandic culture.
Nordvig argues that the story of Ragnarök in the poem Völuspá is particularly rich in descriptions that resemble volcanic activity,[3] possibly influenced by the Eldgjá eruption of the 930s.
[5] Other passages include several verses in the Hallmundarkviða[6] and the creation myth in the Prose Edda, where Nordvig interprets the imagery of fire and ice as attempts to describe phenomena for which Scandinavian settlers in Iceland had no prior vocabulary.
[7] Nordvig's thesis was criticised by Jens Peter Schjødt [da], professor of Nordic religion at Aarhus University, who says Viking Age Icelanders had no reason to hide references to natural phenomena between the lines of poems.
Through Nordvig, the NTF criticised what it perceived as a weak spirituality in Forn Siðr, rejecting commonplace influences from Wicca such as standing in a circle during rituals.
Nordvig became the main architect behind the group's ritual calendar, which allows for diverse practices and uses processions and evocations of Nordic gods to promote a connection to the physical landscape.