Trivia: The lines in the scene at Tommy's house where his mother makes dinner for them were entirely improvised by the actors.
Trivia: In the book Wiseguy, it is stated that even in the gangster world, discipline and order had to maintained. No one could kill anyone they wanted whenever they pleased. Dead bodies were not allowed to be haphazardly left in the streets for all to see. People who had grudges against certain individuals had to sit down with mob chiefs to get their okay to have them 'whacked'. Since Tommy killed Billy Batts and several others without permission, he sealed his own fate. There are similar cases mentioned in the book regarding loose cannons, deadbeats, and snitches and their ultimate demise. Henry put it so in the case of Stacks Edwards: "It was Jimmy who gave the order, but it was Paulie who gave Jimmy the look."
Trivia: Though the film never mentions him, the second son of Henry's mob chief Paul, Paulie Jr., was actually Henry's best friend since youth and even introduced him to Karen. In the film he was replaced with Tommy, played by Joe Pesci. Paul Sr. had three sons with his wife Phyliss: Peter, Paul Jr., and Leonard.
Trivia: Ray Liotta was suggested to director Martin Scorcese by Robert De Niro. When Scorcese asked, 'So who do we get for Henry Hill?' De Niro responded, 'How about that guy from Something Wild?' Similarly, Scorcese recalls Joe Pesci telling him to hire Frank DiLeo for Tuddy by saying, 'Marty, you should get Frank DiLeo for this part. He's perfect.' And the rest, as they say, is history.
Trivia: Although Paul Vario was a large fellow, this did not mean that he could not move fast whenever he wanted to. In the book Wiseguy, it is stated that Henry saw him grab a sawed-off baseball bat from the trunk of his car and chase a nimbler man up five flights of stairs to collect a loan shark debt.
Trivia: When the Hill family were about to begin life in hiding under the Witness Protection Program, Karen's optimism is revealed. In the book Wiseguy, she said something to the effect of 'There'd be no more gangsters, hitmen, and no more cheating girlfriends. I thought maybe it wasn't going to be so bad after all.'
Trivia: Johnny Dio, who is seen cooking steak in a pan in jail is played by Frank Pellegrino, who is also the co-owner of the legendary NY Italian restaurant, Rao's. His real nickname is "Frankie No", due to the utter impossibility of getting a reservation in the restaurant where tables are reserved literally years in advance. Pellegrino also appears regularly in The Sopranos as FBI Agent Cubitoso.
Trivia: Near the film's end, Henry goes and apologizes to Paulie for being busted. Actually, it was not Henry that went to see Paulie; it was Karen. At the time, Paulie had already refused to help bail out Henry due to the drug charges and because of that, Henry was still inside. Paulie actually told Karen that he had to turn his back on Henry. He then gave the money to Karen.
Trivia: Watch Jimmy Conway carefully. He often takes drags of his cigarette, but never exhales any smoke.
Trivia: Both of director Martin Scorsese's parents are in the movie. The old lady that plays Tommy D's mother, and Vinny, who puts too many onions in the sauce