Creator races: Wow, now I really have learnt something, not just something new but also something that has changed my perception of the whole D&D universe. Never having read any of the literature except for game manuals, I'd always supposed humans were the last to arrive. So they predated elves, dwarves, etc? Wow. Are "we" the elder race?
In the Forgotten Realms, yes. Humans are a native species, very hardy and difficult to stamp out - rather like cockroaches

Elves are interlopers from another dimension, Faerie. Orcs were brought from other worlds, at least twice. I'll have a look at others, but I think both dwarves and gnomes claim to be either created or found by their gods. Halflings just sort of appear at some point after the decline of the Creator Races. Half-elves and half-orcs are a mystery, to me at any rate

And as some of the answers to the say quite a few species were created by others.
Question to you boffins: How much is the history and prehistory of Toril drawn from by Tolkien, since we have halflings that seem to be hobbits, etc? Or did LoTR merely provide general inspiration?
I'd say there's a lot of Tolkien in
D&D in general. Certainly halflings, who were even called hobbits in some of the earliest versions before the Tolkien estate started to talk about law-suits and copyright. Then you can get into the argument about how much of Tolkien is really original, because he didn't invent elves, dwarves, or even orcs (orcne appear in Beowulf). Ed Greenwood created the Forgotten Realms as a setting for fantasy stories back in the 1960s, when Tolkien was really becoming very popular in North America if I understand correctly, and I'd be suprised if it wasn't one of his inspirations. At the same time there are definitely others. If Fritz Leiber wasn't among them I'd be absolutely astonished, given the nature of Waterdeep compared to Lankhmar.
Back from the brink.
Like RPGs? Like Star Wars? Think combining the two would be fun? Read Darths and Droids, and discover the line "Jar Jar, you're a genius".
These, in the day when heaven was falling,
The hour when earth's foundations fled,
Followed their mercenary calling
And took their wages and are dead.