Gary Gygax himself, on this forum no less stated he never read Hobbit or Lord of the Rings, that he hated the writing style and could not make it through the books.
He also said/implied that he pulled things out of various mythologies and adapted them and that is where many of his monsters came from in oD&D.
Is that believable? That Gary went read old Germanic folklore and just happened to create Treants that looked just like Ents and had a name that is 99% similar? Not sure anyone can say. Gygax said he didnt steal ideas. Im not sure anyone here has the proof to say otherwise.
Now did he personally dislike them? I think so. But he did read them. He said "In general the "Ring Trilogy" is not fast paced, and outside the framework of the tale many of Tolkien's creatures are not very exciting or different." He can't know the pacing if he never read them. He also said, "These considerations, as well as a comparison of the creatures of Tolkien's writings with the models they were drawn from (or with a hypothetical counterpart desirable from a wargame standpoint) were in mind when Chainmail and Dungeons & Dragons were created."
I am quite certain Gygax said he read and enjoyed the Hobbit, but wasn't a huge fan of LotR: but I'm certain he read them, or more vitally other members of his circle did. D&D was collaborative from the start.
An essay by Gygax in Dragon 95 (March 1985) seems relevant (pp 12-13):
Though I thoroughly enjoyed The Hobbit, I found the “Ring Trilogy” . . . well, tedious. The action dragged, and it smacked of an allegory of the struggle of the little common working folk of England against the threat of Hitler’s Nazi evil. At the risk of incurring the wrath of the Professor’s dedicated readers, I must say that I was so bored with his tomes that I took nearly three weeks to finish them. . . .
“Ent” is interesting; Tolkien took the name from an old Anglo-Saxon word for “giant,” and his treatment of them as sentient trees is inspired. This sort of creature appears in both game systems. “Orc” (from Orcus) is another term for an ogre or ogrelike creature. Being useful fodder for the ranks of bad guys, monsters similar to Tolkien’s orcs are also in both games. . . .
“Hobbit” is another folkword borrowed from legends, but Tolkien personified and developed these diminutive stalwarts extensively. They, and the name, are virtually unique to his works, and the halflings of both game systems draw substantial inspiration from them. . . .
The seeming parallels and inspirations are actually the results of a studied effort to capitalize on the then-current “craze” for Tolkien’s literature.
Taking Gygax at his word, even he acknowledges the derivative character of D&D treants, haflings and orcs. At least at that time, he also didn't profess any dislike for The Hobbit.
Rival tribes of Orcs and Hobgoblins attacking each other against orders.
Absolutely. The orc tribes in Chainmail are even named after Tolkien's orcs (The Red Eye, the White Hand, etc).
playable demihumans were put in to pander to LotR fans, and that pandering paid off!
<snip>
It doesn't really feel like LotR unless you work really hard to make it feel like that.
The biggest influence of Tolkien to me is not specific bits and pieces but that all the races were more relatable. In mythology, the elder races are mysterious and dangerous, not someone you would view as a travelling companion.
I would say that the most Tolkienesque element of D&D is the idea of fantasy "races" as distinct humanesque cultures, rather than as "monsters" who have no comprehensible and rational existence of their own. I regard this as probably the most significant literary achievement of LotR - it takes the idea of the "Fairy Queen" and elves, brownies, kobolds etc and makes them plausible within the conventions of the modern, more-or-less naturalistic novel.
D&D absolutely takes this for granted - that elves and dwarves are just as "naturalised" as humans - and I think it takes it entirely from Tolkien.
D&D's roots are more directly from miniature wargaming than fantasy fiction. And contrary to popular delusion, Tolkien didn't create or single-handedly mainstream the entire genre either. Even within the realm of pulp "fantasy" fiction, stories like Robert Howard's
Conan the Barbarian predate Lord of the Rings by decades...
But the basic fictional framing of D&D owes as much to JRRT as to REH. REH is a principal source of the "adventurer" trope, and also of a fantasy world which is an ahistorical pastiche of historical eras. But JRRT is the source of the adventuring fellowship whose members are of varied "races" which are both (i) legendary elves, dwarves, etc but also (ii) essentially humans in variant guise.
Giant eagles were not his idea. The rukk (roc) is an Arabic myth, and a pretty popular one at that.
<snip>
Were-bears. lycanthropy as a concept existed for thousands of years.
@Celebrim has me blocked, but the quotes of his posts mostly respond to the case of the giant eagles: but for JRRT, why would giant eagles be called out as (i) distinct from rocs, (ii) as being able to talk, and (iii) as "attack[ing] evil creatures which seem to be threatening" and "fairly friendly towards certain dwarves and elves" (AD&D MM, p 36).
And as far as wearbears are concerned, the derivation from Beorn is very apparent in their CG alignment. (Which, as others have said, is not to say that JRRT invented Beorn from whole cloth. It's to assert that, but for Beorn, no CG werebears.)
Where do we get the concept of <snip> The Paladin?
The paladin is not directly inspired by Tolkien - its a combination of history (Knights Templar etc), legend (the healing hands of saintly kings) and fiction (Arthurian etc romances). But one of the best treatments of that archetype in fantasy fiction is Tolkien's treatment of Aragorn.
But it's also cherrypicking.
Isn't that what this thread asks for?