Their answer to existential questions was to throw their lives away slaughtering each other and innocents in battle, so they could drink mead in Valhalla until the Final Battle. The question is Existential. Their answer was nihilist.
> The fact that Vikings chose to create meaning by slaughtering their unfortunate neighbors is a bit beside the point.
Nihilism is specifically about the idea that there is no meaning and no will to create some.
Creating meaning, seeking it, is the inverse of a nihilist answer.
If Vikings were nihilists they would have engaged in a multitude of different activities without justifications rather than creating meaning by all fighting anyway. This fighting they do, despite the fact it won't change anything is an existentialist trait and an existentialist answer. I'd concede it's close to a philosophical suicide.
I am not fluent enough in English and I remember not much from philo 101 so allow me to quote wikipedia:
A pervasive theme in existentialist philosophy, however, is to persist through encounters with the absurd, as seen in Camus' The Myth of Sisyphus ("One must imagine Sisyphus happy")
