As Granier-Deferre had been part of the Exodus (at the age of 13), he was able to add a lot of personal observations to his description of the flight (such as people remaining cheerful despite the tragedy of the situation, nuns picking flowers in a field during a bombing raid, ...)
The director found how to film the end only 24 four hours before shooting it, after listening to the prewritten score by Philippe Sarde.
It is star actress Romy Schneider who contacted Pierre Granier-Deferre and expressed her desire to make a movie with him.
Because Régine, a famous French singer and nightclub proprietor, used to arrive on the set with her own car with chauffeur, the rest of the cast thought at first the production team gave her a special VIP treatment.
Jean Louis Trintignant's character's name is Maroyeur, the same character's name that Jean Gabin had in another Pierre Granier Deferre 's film: La Horse, made three years earlier.