Some vikings were Christian while others were pagan. While Heathenry is called “the religion of the vikings” for this reason and others, it’s not and has never been “the religion of being a viking.”
“Viking” was a very specific occupation similar to “pirate” or even “mercenary.” Very few Scandinavians were vikings the same way very few people today are part of the navy. Trying to understand Heathenry by looking at the activities of the vikings would be like trying to understand Christianity by looking at the activities of the US military: It’d leave us with a very aggressive and skewed impression of what people actually valued and believed in.
Our stereotype of vikings is also inaccurate to the way vikings actually were. The image of bloodthirsty, axe-wielding “viking warriors” is actually a reflection of the Varangian Guard. This was an elite military force whose members protected and obeyed the Byzantine emperor even unto death. Varangian guardsmen were known for their massive statures, axes, long hair, fearlessness in battle, ruthless combat behavior, intense sense of duty, and unwavering loyalty. But this loyalty was to the Byzantine throne, not to pagan gods. We can’t say for sure how much their activities reflected pagan values, considering many of the guards were also Christian, and considering their warrior culture was likely shaped by the forces they served, rather than by their spirituality.
Many Heathens today incorporate a degree of viking-ness into their practice simply because the interest overlaps with their spirituality and lifestyle. If this brings you joy, I encourage you to embrace it. But if it doesn’t, then there’s no need to add it in.