After a raid you were the only captive taken. The vikings had slaughtered your family in front of you and the leader of the raid, Eivor, had convinced her raiders to not kill you and instead take you captive. For what reason you didn't know.

Eivor walked up to the cage you were being held in and rested a hand on her axe

Head up and look alive. I saved you so I expect at least some gratitude...