Conan the Librarian!
The tales, set in an ancient time described as being between the sinking of Atlantis and the beginning of recorded history, usually combined swordplay with an element of the supernatural.
Another theme was the barbarian vs. the civilized man, with the latter proving inferior to the former.
Howard's first Conan story depicted him as a king, a post he rose to by slaying the previous, decadent monarch, but later included his earlier life as a wanderer, thief and soldier. He was never quite a hero, though in general if he wasn't on the side of right, he was on the side of not-as-bad.
Howard's writing, while it would never be mistaken for Shakespeare, sometimes had poetry to it, which is painfully apparent when you read Conan tales by other hands. Howard also had strong ideas about history and philosophy, which he sometimes incorporated into his fictional historical narratives.
Two stories I particularly enjoyed when younger were "The Tower of the Elephant" and "Rogues in the House." In the first, Conan scales a sorcerer's glass-walled tower to steal a jewel known as the Heart of the Elephant, where he encounters the otherworldly being who is the jewel's true owner. In the second, Conan is freed from prison by an aristocrat to assassinate a blackmailing priest in his booby-trapped home, only to face an inhuman, possibly supernatural menace.
Unfortunately, the first Conan film drew very little from Howard's stories (there are elements from "Queen of the Black Coast," plus a few iconic images from other stories, devoid of original context, such as the tower scene and a crucifixion; the villain's name, Thulsa Doom, came from a non-Conan Howard story, but the character himself bore little resemblance), and the second took nothing besides the Conan name.
Arnold's Conan was even a bit of a passive, posturing, musclebound wimp by comparison. The "literary" Conan came from a frozen northern country, where he feuded with rival kingdoms, before leaving in search of adventure and fortune. He wasn't verbose, but neither was he monosyllabic. He wasn't educated in the civilized sense, but he was shrewd and self-reliant.
The new Conan film seems similarly divorced from the stories, though maybe his character is intact.
Howard's original Conan stories were rearranged and supplemented by other Howard stories, rewritten to change the protagonist's name and milieu to Conan's, and story fragments completed by other authors as well as new stories by L. Sprague de Camp and Lin Carter (plus one entry by Bjorn Nyberg) to create a unified 12-volume saga. Many of them have been adapted into comic book form.
If you're curious about the original stories, all the Conan fiction written by Howard has been collected in three volumes, including variant drafts and incomplete fragments, as "The Coming of Conan the Cimmerian," "The Bloody Crown of Conan" and "The Conquering Sword of Conan" (Del Rey). There's also a one-volume collection (sans variant drafts and Howard's only Conan novel, "The Hour of the Dragon"), published as "Conan the Barbarian" (Prion).
Howard wrote many other stories in his short, tragic life, from modern day supernatural horror to regional Texas adventure. A particular favorite is "Pigeons from Hell," which was adapted for TV in the 1950s and whose admirers include Stephen King.
For a look at Robert E. Howard the man, see the film "The Whole Wide World," based on an ex-girlfriend's memoir and starring Vincent D’Onofrio and Renee Zellweger.