Kayleigh Brennen Brady

Berserkers are not unknown to the Viking people. They are usually short-lived and so they are considered to be dead walking among the living. They are stripped of their names and families. They are used to terrify enemies with their ferocity in battle. This Berserker does not die quickly, and his chieftains and kings must then try to control this killing power. He is sent to Constantinople to be a guardian to a Byzantine prince.
From there he travels to Kiev where his rare talent is used again. This fiction is thickly sprinkled with true historical events and figures. Can you spot them all?