Frank Capra's first cut of the film ran for 6 hours. The first public preview took place in Santa Barbara when the film ran for 3 1/2 hours. Re-shooting and re-cutting followed immediately after this disastrous preview.
Its budget was $1.5 million and the film ultimately cost almost twice as much as that, a sum significantly higher than most of Columbia's other output combined.
The film took 10 months to make in total, though in between gaps in filming Capra's crew managed to squeeze in Richard Boleslawski's Theodora Goes Wild.
Many scenes were shot at the Los Angeles Ice and Cold Storage Warehouse where Capra had 13,000 square feet of refrigerated space at his disposal. Nearly four miles of ammonia piping cooled the soundstage. Cinematographer Joseph Walker experienced a lot of problems in this location as the extreme cold created static electricity which damaged his film stock.
The California State Censor Board insisted on having two signed affidavits from Columbia that the model doubling for Jane Wyatt in her nude bathing scene had her breasts covered. The affidavits were duly supplied though the model in question apparently was indeed bare-breasted, though as the scene is in long shot it's virtually impossible to tell.
Studio head Harry Cohn didn't like Sam Jaffe's performance as the High Lama and insisted that Capra shoot it with another actor. Capra had to submit to this request and a test with Walter Connolly was made, with Cohn even insisting on an expensive new set being built specially for it. Despite loading the dice in Connolly's favor, the consensus was that his test wasn't anywhere near as good. So Jaffe won the part back, though he still had to re-shoot all his scenes as they were deemed to be far too lengthy and wordy.
According to assistant director Andrew Marton, a lot of the footage of Ronald Colman making his own way through the Himalayas is stock footage taken from two German mountaineering films.
After initial reservations about Frank Capra's method of directing, Ronald Colman would eventually come to rely on him and the two would experiment with improvisations.
Frank Capra hated screen tests; scripts were developed with specific actors in mind. Ronald Colman was first choice to play Conway from the very beginning. It was only over who should play the High Lama that he had problems and had to resort to screen tests.
The Lamasery set was, at the time, the largest single standing set in terms of square feet built for a motion picture of the sound era. The set was built on the Columbia ranch in Burbank with the rear of the Lamasery backing up to the intersection of Verdugo Avenue and Hollywood Way.
The characters portrayed by Jane Wyatt (Sondra) and Edward Everett Horton (Lovett) do not appear in James Hilton's novel but were added to the screenplay for romantic interest and comic relief.
Despite the persistent rumor that Walter Connolly was tested for the role of the High Lama was vehemently denied by Frank Capra. Only two actors were considered for the role before Sam Jaffe. English actor A.E. Anson was actually tested but died two days after the it was made. Henry B. Walthall was scheduled to be tested but died before one could be made. The third test was of Jaffe, and he got the part. Capra has been quoted as saying that Connolly was considered for the Thomas Mitchell role, but was committed to another project. Capra added that Connolly and Charles Laughton, who was also rumored for the part, were both too fat to play a 200-year-old ascetic.
Soundman Edward Bernds came up with the idea of achieving a faster, barbaric tempo for the previously slow-moving refueling scene by having the tribesmen hack off the tops of the gasoline cans with bayonets and slosh the gasoline out. Frank Capra liked the idea and included it.
The part of the paleontologist was not in the original novel but was developed for Edward Everett Horton by Frank Capra. Horton improvised the scene when he is startled by the mirror in the lacquer box when Capra asked him to suggest some business for that scene.
The trivia items below may give away important plot points.
Originally there was an opening prologue in which a weary Ronald Colman on a cruise ship is prompted to tell his amazing story of the land of Shangri-La. Although alluded to in the closing passages of the film, no footage of this prologue has ever been found. Frank Capra claimed he burned it.