Almuric by Robert E. Howard

A restless, ill-fitting man is swept from his old life to a savage, prehistoric alien world where survival depends on quick learning, raw strength, and ruthless adaptability; amid vast jungles, brutal beasts and warring tribes he hones himself into a fearsome warrior, forges fierce loyalties, wins love and leads a desperate struggle against monstrous foes and oppressive forces, ultimately embracing the violent freedom and harsh justice of his new home.

Purchase from Bookshop.org