You might also consider /r/Norse (which has a larger group of subscribers than /r/Mythology) - all dedicated to understanding just the sort of question you are asking. This aspect of pre-conversion belief is extremely complex, and it was likely influenced by the Christian concept of end times - but even that assertion is controversial and causes some Neo-pagans to blanch, since they would prefer to see the Norse account of the end of the world as strictly an indigenous story. As with all things, source criticism is needed as you prepare to receive all sorts of points of view, but the subject you raise requires a triple dose of caution.

hi! you may be interested in a few previous posts in this sub

• Want to learn more about Norse mythology (specifically Ragnarök)

• Was the similarity between Ragnarok and the events of Revelation noted by missionaries or the missionized during Scandinavia's conversion to Christianity? Was the common theme ever exploited to win converts?

• Was Christian influence responsible for the creation of the idea of Ragnarok in Norse/Viking mythology?

• Did adherents to the Norse religion believe they were living before or after Ragnarok?

• When is Ragnarök meant to occur?

You might consider also asking /r/Mythology, especially since Ragnarok is literally a myth (and furthermore, in Norse mythology, Ragnarok is set in the future).