in the 1920s i think, there was a big tournament in Barcelona. and the organizers asked the funniest GM there ever was, Savielly Tartakower to just make up a new opening. Just make up a new opening, how hard can it be? And once you do, name it after Catalonia, in honor of the region's chess history.
Well, he did. What's more, it was pretty good. A bunch of world champions and other top GMs played it and liked it, and today it's part of Carlsen's repertoire. It has a reputation of being a very difficult, theoretical opening to learn because there are a lot of moving parts and the advantages you get are very positional (i.e. you can have the same pieces as your opponent, and not have an immediate checkmating attack, but be absolutely winning). To my knowledge Tartakower didn't play it all that much comparatively.
There are other variations named after Tartakower, but he is also often credited with naming the Orangutan opening, an offbeat (some would say "unplayable") opening allegedly named because he visited a zoo on the way to a tournament and so admired an orangutan there that he resolved to name an opening after it. He's also known for quotes like "The blunders are all there on the board, waiting to be made." and "A match demonstrates less than a tournament. But a tournament demonstrates nothing at all." What I'm trying to say is, he's an absolute king.
