It's largely forgotten now — but there was a time when the mere mention of Brooklyn would produce a cascade of laughs. It was like saying "woman driver" — surefire guffaws. Everybody from Brooklyn was supposed to be a character.
Every platoon in every war movie had one wise guy from Brooklyn in it. Brooklyn natives spoke funny. They said, most famously, "youse guys." At a time when African-Americans, Asian-Americans and Hispanics barely existed — visibly — in movies or on radio or television, Brooklyn was the all-purpose stand-in for our great American ethnic diversity.