Right, which is why I said I'm assessing D&D through the lens of hindsight. Whatever the influence Tolkien had at the inception (more on this in a moment), my point is that the role D&D has today is basically dependent upon its wholesale incorporation of Tolkien.
No, the goblinoids in D&D are lifted from Tolkien, as are the undead, see here:
http://deltasdnd.blogspot.com/2012/03/wraiths-through-ages.html and
http://deltasdnd.blogspot.com/2012/03/back-from-dead.html.
When wraiths were first introduced to Chainmail, they were simply called Nazgul. Their characteristics were clearly lifted from the Nazgul. And wights were all but expressly based on barrow-wights. Indeed, I'm not sure the word "wight" as an undead creature was used in fantasy before Tolkien, and there he was lifting a specific translation of a saga that used "barrow-wight" for a draug.
This is the sort of thing that rustles my jimmies on the subject. The rule isn't "anything that existed as a vaguely associated concept in folklore before Tolkien wasn't copied from Tolkien"; and if that is the rule, it's not clear to me why "trolls" are attributed to Three Hearts, Three Lions when trolls are endemic in folklore. Though the regenerative aspect seems Poul Anderson's creation (I think? it's not even that central in the story as I recall), Anderson's gloss on troll seems much less distinctive than Tolkien's gloss on wights, wraiths, goblins, etc. The impulse to credit Anderson and derogate Tolkien smacks of a guilty conscience!
Anyway, Gygax is great, and I love that he put together Appendix N, and he obviously was very well read (better read than me!) in the fantasy genre, and a skillful assimilator of many sources. I just think downplaying Tolkien is kind of lame.
I had forgotten to put balrogs in the list, as they apparently were a monster included in the pre-lawsuit version of original Dungeons & Dragons and then removed from the bestiary (though a few mentions of balrogs remained elsewhere). On the other hand, I had added
hobbits halflings when they in fact were not included in the bestiary (where gnomes, dwarves, and elves are listed), just as a player-character race. Moving wights and wraiths as well yields the following list:
Reality: Men
Classical Mythology: Medusae, Gorgons, Manticoras, Hydrae, Chimeras, Minotaurs, Centaurs, Dryads, Pegasi, Elementals
Medieval Legends/Folklore: Goblins, Kobolds, Hobgoblins, Ogres, Giants, Skeletons, Ghouls, Spectres, Cockatrices, Basilisks, Wyverns, Dragons, Gargoyles, Lycanthropes, Unicorns, Nixies, Pixies, Gnomes, Dwarves, Elves, Hippogriffs, Rocs, Griffons, Djinn, Efreet
Tolkien: Orcs, Wights, Wraiths, Treants, Balrogs
Other Fantasy/Horror Literature and Film: Trolls, Zombies, Mummies, Vampires
Original: Gnolls, Purple Worms, Invisible Stalker, Ochre Jelly, Black Pudding, Green Slime, Gray Ooze, Yellow Mold
At the end of the bestiary, Gygax briefly lists a few more creatures, including gelatinous cubes, but does not provide stats for them. The first three supplements released for original D&D (Supplement I: Greyhawk, Supplement II: Blackmoor, and Supplement III: Eldritch Wizardry) did include a variety of new monsters, and these could be original creations (e.g. beholder, gelatinous cube, rust monster, mind flayer), extinct animals from reality (e.g. dinosaurs) or giant versions of real animals, from classical mythology (e.g. titans, harpies), from medieval legends/folklore (e.g. will o'wisps, couatl), or less frequently from non-Tolkien fantasy/horror/SF literature (e.g. displacer beasts, shadows). However, I don't think there was a single additional monster added from Tolkien (and Supplement I, at least, must have been released prior to the threatened lawsuit, since it still mentions balrogs, hobbits, and ents).
Again, Tolkien's popularity also resulted in players having the option of playing Tolkienesque elves, Tolkienesque dwarves, and
hobbits halflings, but did not affect even the character classes, and the fundamental game mechanics are derived from miniatures wargaming combined with many original creations of Gygax and Arneson as well as intended player-character behavior that owes heavily to Robert E. Howard's and Fritz Leiber's sword-and-sorcery writings.
Actually gnolls came from Lord Dunsany books.
One story of Dunsany's featured a creature called "gnoles" but this seems to have been coincidental, as
remarked upon by Gary Gygax in 2003.