Philip Jos Farmer was an American author, principally known for his science fiction and fantasy novels and short stories. Farmer is best known for his sequences of novels particularly the World of Tiers (1965-93) and Riverworld (1971-83) series. His work is celebrated for its innovative use of sexual and religious themes, his fascination for and reworking of the lore of legendary pulp heroes, and his occasional tongue-in-cheek pseudonymous works penned as if by fictional characters.

Farmer's ingenuity extended to the amalgamation of both authentic and fictional characters, worlds, and authors. His Wold Newton family books create a network that binds classic fictional personages as actual relatives, a lineage born from an extraterrestrial plot. His novels The Other Log of Phileas Fogg and Doc Savage: His Apocalyptic Life are prime examples of early literary mashup novels. Literary critic Leslie Fiedler lauded Farmer's unique blend of the naive and the sophisticated in his unusual combination of theology, erotica, and adventure.