but Tolkein introduced Dwarves as the plural of the Dwarf as a race. I couldn't possibly remember where I heard that.
There's a number of different versions of the tale. Even from his own mouth, in subsequent interviews. Some say that as he was making up entire languages and mythologies (however much inspired by pre-existing ones), he was entitled to make up "Dwarves" as a race pluralisation in his fiction, distinct from "Dwarfs" as a race pluralisation in any prior fiction (or as a potential pluralisation to be used with very real groups of humans-of-restricted-height).
I quite like the one (which may or may not be linked with the above, or else that it was just an error he made but didn't feel like reversing) where his proofreaders told him he'd used the wrong word throughout the first work of his that they were publishing. They told him that it was defined otherwise in the Oxford English Dictionary, whereupon he (with truth behind him) informed them that he had
written (for!) the Oxford English Dictionary.
It's also a variation that existed before Tolkien, but peepul roat thyngs funili sumtymes bak žen...
For anyone who is bothered, though, it's generally accepted that "Dwarfs" is the plural assigned to multiple Dwarf(-like) beings straight from the original Germanic mythologies (without Tolkienesque ramifications, and including 'human midgets' - properly or otherwise), whilst "Dwarves" is the plural assigned to those that come via Middle Earth territory (including D&D), although I've seen Warhammer Fantasy use
both versions so I'm not sure which (if any) is the non-canonical one for that heavily Tolkien-inspired world.
Add to that "Dorfs" as this forum's own 'in-joke' flavour for our Fortress-type dwarfish/dwarven beings. They are inspired both by via-Tolkien and not-via-Tolkien (c.f. Disney's
seven dwarfs, who seem to be the zeroth immigration wave to their local site), and so this little variation is as arguably as good a variant as either of the others, in context...
And "Dorf" also means (approximately) "Village" or "Hamlet", and the link between a small settlement and a small
settler isn't too huge a jump of imagination.