- Acting for Two: As part of the "legend" surrounding Billy The Kid, Emilio Estevez plays both Billy and "Brushy" Bill Roberts (who claimed to be him), the latter of whom is left uncredited in the finished film.
- Billing Displacement: Kiefer Sutherland (Doc) is credited second on the boxart (with his face at the top of the poster) and in the credits of the film. In the actual movie, Doc's not even in the film for an hour before he's shot and killed by Garrett and his men during the ambush at Stinking Springs.
- Breakaway Pop Hit: The film is most likely only remembered these days for the Bon Jovi title track "Blaze of Glory". While the movie itself debuted to tepid reviews and a weak opening (coming in third on its opening weekend behind Ghost and Presumed Innocent), "Blaze" was a #1 Billboard Hit, nominated for an Academy Award (for Best Original Song) and spawned a top-selling solo album of the same name.
- Dawson Casting: Emilio Estevez was twenty-seven when he played the twenty-one year old Billy.
- Killed by Request: It has been reported that Kiefer Sutherland, faced with scheduling conflicts, refused to return unless his character died in the "Stinking Springs Shoot Out". Writer John Fusco fought against this demand, but ultimately rewrote the scene to accommodate Sutherland's schedule.
- The Other Darrin: The character of Pat Garrett was played by Patrick Wayne in the original film, and by William Petersen here.
- Underage Casting: Christian Slater was twenty when he played the twenty-five year old Dave.
- What Could Have Been: There was originally intended to be a sequence where Chavez is riding on a horse while Billy fires a weapon near him. When it came time to shoot the scene, the horse got spooked when Emilio Estevez fired his weapon and knocked Lou Diamond Phillips off, then dragged him along the ground with a noose around his neck and tied to the saddlehorn, nearly killing him in the process. As a result, the scene was never refilmed and was left on the cutting room floor.
- Written-In Infirmity: The scene where Arkansas Dave Rudabaugh puts a knife through Chavez' arm was added due to Lou Diamond Phillips' breaking his arm during filming.
Trivia / Young Guns II