The presence of a 'thieves guild' as, like, an organized public corporate body with a monopoly on crime is such a weird fantasy trope.
Especially when the text seems to unironically position them as, like, 'criminals but not that bad. Always looking out for each other and never really hurting anyone who doesn't deserve it.'
The trope comes from Fritz Leiber as far as I know, and it was originally meant to be tongue-in-cheek. (He was like the proto-Terry Pratchett.) And they were quite evil, but it's old-school sword&sorcery, so the heroes are rather amoral, as well.
But is there a thieves guild with a legitimate monopoly on theft outside of the Discworld? In normal fantasy, they're bribing the government and murdering competitors, right?
Also, I think a big reason for making them not that bad is RPGs. Players might want to play a rogue, but not a bad guy.
Actually, regarding the last point, that player is me. I just remembered that I hated the Skyrim thieves guild, because the first quest is to intimidate shopkeepers. But realistically, a thieves guild would devolve into a protection racket in less than a minute.
See this is just a fundamental weakness with the whole 'each class has a sort of institution and the arch of the PC is rising to the top of theirs' paradigm imo - 'forever on the run from the really nasty organized criminals because they drew some line in the sane and didn't kill someone/freed some slaves that were going to make the boss a lot of money/whatever' is one of the most archetypally plucky charming rogue situations to be in!
Hah, that's a classic rogue background, in my experience. The fighter equivalent is "deserter from the army", and they both slap.
As for where the Thieves' Guild came from, Fritz Leiber did indeed invent it. My theory is that The Court of Miracles in The Hunchback of Notre Dame (not so much the novel, but specifically the 1939 film, the one with Charles Laughton as Quasimodo) was a major influence both for Leiber's story and the trope as a whole. See here:
In a nutshell, Fritz Leiber invented the Thieves’ Guild, and D&D pilfered it. As for where Leiber got the inspiration, we can certainly spec
Something even older I have read a little bit about is the Coquillars, an organization of unemployed mercenaries resulting from the end of the Hundred Years War who worked together on counterfeiting, gambling scams, pimping, organized robberies on highways + estates, and other crimes.
Allegedly they did have their own opaque jargon and oaths of loyalty and silence. They also absorbed crooked priests, merchants, and lawyers into their faction.
Sadly a lot of the information on them is in French.
