I’ve been reading Kull: Exile of Atlantis and Conan the Barbarian. I love them, but I am wondering if there’s a larger non-short story book by Robert E. Howard?
Howard wrote only one full-length novel that was published in his lifetime, which he titled The Hour of the Dragon. Many printings rename it Conan the Conqueror. It was serialized in Weird Tales in 1935–1936, starting with the December 1935 issue. It is not a fix-up, per se, but is very episodic.
Besides this, Howard did, however, write a number of intermediate-length genre stories, about Conan and otherwise. The longest non-novel works published by Howard appear to be the planetary romance "Almuric" (which was labeled as a "novel" when it was serialized in Weird Tales, but is really more of novella length), the Conan story "The People of the Black Circle" (which takes place in India and Afghanistan and is one of Howard's most popular works, although I don't personally care for it), and the modern story "Skull-Face" (which has some interesting fantasy elements, but, as you might expect from a Howard story set in present-day London, has a lot of racist ideas).
According to a search by author and title type on ISFDb (you may need to be logged in to run it), there are 7 novels credited to Howard, however 2 of those are non-SF, and 3 were completed by others after his death.
The 3 novels that were completed by others after his death, for which credit is shared are:
- The Treasure of Tranicos (1980) by L. Sprague de Camp and Robert E. Howard
- Conan: Flame Knife (1981) by L. Sprague de Camp and Robert E. Howard
- King Conan and the Stygian Queen: Beyond the Black River (2016) by Robert E. Howard and Jess Eden Thornton
The two non-SF novels are: