Trivia: The Iron Giant has only 53 words of dialogue in the entire film.
Trivia: When Hogarth first goes into Dean's house, there's artwork all about. One of which is a painting on the wall that has the common animation Easter egg of A113, a famous animation studio, which has that number appear in many animated films. Later in the film, a farmer is showing Mansly his half-eaten car, and the license plate also shows A113 but partially eaten.
Trivia: After Mansley's car is eaten by the Giant and disappears, Mansley is trying to get Marv to look at it but doesn't realise it's gone yet. Marv then asks, "What are we looking at here, Manly?" leaving out the S in Mansley to call him Manly. This was a mistake on the voice actor's part, but Brad Bird liked it and thought it appropriate for the character, so left that take in.





Answer: He was in the military. Probably died in the military.