Robert Holdstock 
Bull Chief [EPUB ebook] 

In the Celtic tribal lands of Connacht, he came of age among the Druids and headhunters and the ghosts of the great Bronze Age people of Danann.He fought his savage, bloodthirsty way to the west, as a naked warrior who had rejected the tribal laws. And there Arthur, Warlord of the Britons, came to find him, to exploit his skill and invulnerability in the war against the Saxons.Yet Swiftaxe, the Berserker, wanted one thing only; to break the curse that condemned him to his life of frenzied violence and bloodlust.But until the might of the Saxons was destroyed, he would never be free . . .