A ferocious young man who is devoted to avenging his father's death at the hands of Askeladd, and is tricked into joining his band in hopes of defeating him in a fair fight. He is the son of Thors, the most renowned Jomsviking warrior until his defection, and is related to the leadership of the Jomsvikings through his mother Helga, daughter of chief Sigvaldi and Thorkell's niece.

After his father's death, Thorfinn grew up on the battlefield and became a skilled warrior. His style is emphasized by dual-wielding two knives, as well as using throwing knives, and he has impressive durability.

Thorfinn is the fictionalized version of his historical counterpart, Icelandic explorer Thorfinn Karlsefni.

(Source: Vinland Saga Wiki, edited)