In fairness, Lovecraft's works were stupidly long and obscenely racist, even for the 1920s. August Derleth is the one who created the Elder God mythos.

Still, don't call yourself a fan of the Cthulhu mythos (Or Lovecraft, for that matter) when you can only name a single character that isn't even a major one (As far as I have read, Cthulhu only appears on a short story that appeared on Weird Tales, and that's it). Hell, most of these supposed "Lovecraft" couldn't even mention other big characters like Shub Niggurath (Iä! Shub-Niggurath!) or even the Great Old Ones.