Tolkien's world-building and invented languages remain unparalleled. He didn't just write stories; he crafted an entirely new reality that has brought so many people together. That's why he's the greatest author the world has ever seen. Period.
@anon_opin He should probably share the credit with all the creators of the Norse myths he looted with abandon and chuck Snorri Sturluson a few kronor. I do love Tolkien though.