Star Trek: 10 Things You Didn’t Know About Quark
4. The idea for his character came from a western
If you thought that Michael Curtiz tie-ins would end with Casablanca, you were wrong.
According to Michael Piller, they settled on having a bartender character aboard Deep Space Nine early on in the show's development. For inspiration, they looked at Dodge City, a 1939 western starring Errol Flynn and directed by Curtiz. There was a character played by Frank McHugh in it called Joe Clemens and he was the local bartender.
Piller and the rest of the writing staff liked that idea and started conceiving the character of Quark around Clemens, but he eventually evolved into something entirely unique. However, it makes a lot of sense to think about Deep Space Nine as a frontier town in the Wild West and Quark's Bar as the saloon where all the shady characters congregate. The metaphor works in more ways than one, whether the creators initially had that in mind or not.
First Casablanca and now Dodge City, I'm starting to think DS9 perhaps should have included Curtiz's name in the end credits.