During filming of the immense coronation scene in the Forbidden City, Queen Elizabeth II was in Beijing on a state visit. The production was given priority over her by the Chinese authorities and she was therefore unable to visit the Forbidden City.
Most of the exterior and interior scenes of Pu-yi's mansion during his years as a puppet emperor for the Japanese (most notably the "Coronation Ball" scene) were filmed at the Imperial Palace in Changchun, where the real Henry Pu-yi lived from 1934 to 1945. The mansion is now a museum.
According to director of photography Vittorio Storaro in Visions of Light (1992), he used the phases of light to represent different stages of the emperor's life. Red, the color of the blood that starts the flashback and the opening doors it cuts to, represents birth. Orange is the warm color of his family and the forbidden city. Yellow is the color of the emperor's identity and the sun. Green, the color of the tutor's bike and hat, represents knowledge. The forbidden city only has the first three colors because it is a limited portion of reality.
The first feature film granted permission by the Chinese government to be filmed in the Forbidden City. A documentary produced and directed by Lucy Jarvis for NBC Films Ltd. in 1973 named "The Forbidden City" was the first western film permitted to film within the Forbidden City.
1,100 schoolchildren were brought in to play Red Guards who composed the Cultural Revolution march (1967). Bernardo Bertolucci had problems instilling the right amount of anger in them, as none of them knew of the attitudes of the Cultural Revolution.
Two thousand soldiers had the front of their heads shaved in order to play Qing banner men. They were persuaded to do so by their officers who convinced them that it show friendship to the Italians and British. They were given a bonus of $3.50.
Bernardo Bertolucci proposed the film to the Chinese government as one of two possible projects - the other was "La Condition Humaine" by André Malraux. The Chinese preferred this project, and made no restrictions on the content.
Hairdresser Giancarlo De Leonardis imported 2,200 pounds of human hair to make the elaborate wigs needed for the court. For the coronation scenes, his staff spent ten days training fifty Chinese to pin wigs and plaits onto two thousand extras in under two hours.
The 250-acre Forbidden City, built in the early 15th century with high walls up to 50 feet thick, provided an excellent soundproof filming environment - although the Chinese crews were unused to making films with live sound recording.
An Italian chef was brought in to cook for the international cast. He brought with him 22,000 bottles of Italian mineral water, 450 pounds of Italian coffee, 250 gallons of olive oil and 4,500 pounds of pasta.
Ying Ruocheng, who played the governor of the prison in the movie, is a Manchurian himself. His grandmother's family name is also Aisin-Gioro, she's a member of the royal family of Qing dynasty. Ying is actually a Manchurian name, simplified from Heseri, which also is an important family in Qing's history. At the time when the movie was made, Ying was the deputy minister of the culture ministry of Chinese government.
Yuan Jin: the real-life Chinese prison governor who was responsible for the real Henry Pu-yi's rehabilitation, appears in the scene where Pu Yi receives his pardon. Yuan Jin calls Pu Yi's name ("Aisin-Gioro Pu Yi!") over the microphone. As Pu Yi steps forward, the pardon is read aloud by Ruocheng Ying, who plays Yuan Jin's role in the film. John Lone shakes hands with Yuan Jin before receiving the pardon.