The science fiction novels of Edgar Rice Burroughs (1875-1950) are clearly the literary sources of Norman's Gor novels. From Burroughs's Mars series and his later Pellucidar series, Norman recreates the powerful men, the sexually exciting women, the strange mixture of primitive and sexually advanced peoples, the odd and sometimes physically improbable beasts (Burroughs's "Bos" becomes Norman's "Bosk"), the powerful protagonist from another world who gets out of impossible scrapes through sheer brute strength and courage (even the names John Carter and Tarl Cabot are somewhat similar).

In At the Earth's Core (1922), for example, Burroughs imagines a counterEarth, Pellucidar, that is ruled by reptilian creatures who are more advanced and intelligent than men; in Gor, the antlike Priest-Kings rule, and they withhold military technology from the men of Earth, who are used by the Priest-Kings to people their land. However, the humans of Burroughs's Mars and Pellucidar...