Cary Grant got $450,000 for this movie - a substantial amount for the time - plus a percentage of the gross profits. He also received $315,000 in penalty fees for having to stay nine weeks past the time his contract called for.
Cary Grant was initially reluctant to accept the role of Roger Thornhill since at 55 he was much older than the character.
James Stewart was very interested in starring in this movie, begging Alfred Hitchcock to let him play Thornhill. Hitchcock claimed that Vertigo's lack of financial success was because Stewart "looked too old". MGM wanted Gregory Peck, but Hitchcock instead cast Cary Grant, who, ironically, was actually 4 years Stewart's senior.
William Holden was suggested to play Roger Thornhill, but was never actually offered the part.
Ernest Lehman became the film's scriptwriter following a lunchtime meeting with Alfred Hitchcock, arranged by their mutual friend, composer Bernard Herrmann. Hitchcock originally wanted him to work on his new project The Wreck of the Mary Deare (which was eventually made instead by Michael Anderson), but Lehman refused. Hitchcock was so keen to work with him that he suggested they work together on a different film using Mary Deare's budget (without MGM's approval) even though he had only three ideas to set Lehman on his way: mistaken identity, the United Nations building, and a chase scene across the faces of Mt. Rushmore.
Alfred Hitchcock couldn't get permission to film inside the UN, so footage was made of the interior of the building using a hidden camera, and the rooms were later recreated on a soundstage.
Alfred Hitchcock had planned a sequence where Roger Thornhill (Cary Grant) hid in Abraham Lincoln's nose and had a sneezing fit. Park officials would not allow this to be filmed, but Hitchcock tried again and again. Finally, someone asked Hitchcock how he would feel if it were the other way around and Lincoln was having a sneezing fit in Cary Grant's nose. Hitchcock immediately understood and the scene was never filmed. However, "The Man in Lincoln's Nose" was used as a "gag" working title.
Alfred Hitchcock planned to shoot a scene in the Ford automobile plant in Dearborn, MI. As Thornhill and a factory worker discussed a particular foreman at the plant, they would walk along the assembly line as a car was put together from the first bolt to the final panel. Then, as the car rolled off the line ready to drive, Thornhill would open the passenger door and out would roll the body of the foreman he had just been discussing. Hitchcock loved the idea of a body appearing out of nowhere, but he and screenwriter Ernest Lehman couldn't figure out a way to make the scene fit the story, so it never came to fruition.
Alfred Hitchcock: [bathroom] Thornhill hides in a bathroom three times.
Alfred Hitchcock: Hitchcock arrives at a bus stop (during the opening credits) but gets there a second too late and the door is closed in his face. He misses the bus.
James Mason suffered a severe heart attack shortly after filming ended.
According to the book "Haunted Idol: The Story of the Real Cary Grant" by Geoffrey Wansell, Cary Grant wanted Sophia Loren to play the part of Eve Kendall but she turned the role down. Seven years later Sophia Loren played a role very similar to Eve Kendall in Stanley Donen's Alfred Hitchcock-inspired thriller Arabesque opposite Gregory Peck - MGM's original choice for the role of Roger Thornhill.
According to the book, "Alfred Hitchcock: A Life in Darkness and Light", by Patrick McGilligan, Yul Brynner was a first consideration for the role of Phillip Vandamm.
Among the problems that the Production Code found with this film was the effeminacy of the henchman Leonard (Martin Landau).
During their escape, Roger says to Eve, "I see you've got the pumpkin," meaning Vandamm's statue containing microfilm. The line references the 1948 Alger Hiss case, in which Whittaker Chambers led federal agents to government microfilms, allegedly supplied to him by Hiss, that Chambers had hidden in a pumpkin on his farm.
Edward Platt who plays Larrabee in 'North By Northwest' did NOT play Larrabee on 'Get Smart.' He played 'The Chief'
Eleven years after being mentioned in Rope as making an excellent villain, James Mason was finally cast by Alfred Hitchcock as such in North by Northwest.
Famed art director/special effects artist Albert Whitlock who worked on several Hitchcock films (not this one) painted a painting of Mount Rushmore and superimposed the face of Alfred Hitchcock into the rock sculptures on the mountain as a joke. The painting exists in a private collection.
If the fictional Thornhill had plans, as he stated, to attend the Winter Garden Theatre when the movie opened in the U.S. in July of 1959 (when he was kidnapped from the Oak Room), his tickets would have been for "West Side Story." But Thornhill, possibly, implies it was "My Fair Lady" that he had tickets for when he started to sing, while drunk in the Mercedes, "I've grown accustomed to your bourbon..."