Thorkell is a Jomsviking general and brother of the Jomsviking Chief. A giant man who loves combat he defects from the Danish army to become a mercenary for the English, believing that fighting his fellow Vikings will give him a better challenge. This same love of war leads him to support Prince Canute's bid for kingship of the Danes. Before Thors' defection he works with and highly respects the man, and bears a fondness for his son Thorfinn in the main plot. He duels twice with Thorfinn and dominates each time, though he loses two fingers in the first duel and an eye in the second. In battle, Thorkell typically wields a pair of axes as his primary weapons, but his greatest asset is probably his vast physical strength. During a skirmish with Askeladd's band, he hurled a spear with such force that it skewered three man at once, despite having been thrown from several hundred feet away. Thorkell's character is based on Thorkell the Tall, a historical Jomsviking lord who is a mentor to Canute in the Flateyjarbók.
Joined Canute as his servant after seeing him change in front of Askeladd and Thorfinn.