The Longest Day is a 1962 epic war film based on Cornelius Ryan 's book The Longest Day (1959), about the D - Day landings at Normandy on June 6, 1944, during World War II. The film was produced by Darryl F. Zanuck, who paid author Ryan $175,000 for the film rights. The screenplay was by Ryan, with additional material written by Romain Gary, James Jones, David Pursall and Jack Seddon. It was directed by Ken Annakin (British and French exteriors), Andrew Marton (American exteriors), and Bernhard Wicki (German scenes).
when was the film the longest day made
1962