At first, it seemed that the film would be made on location in Thailand, but even after script revisions had been made, negotiations between the production company and the Thai government failed. They could not reach an agreement about the script's final content, and the production was subsequently denied permission to film in Thailand. The Thai authorities maintained that there were still too many historical inaccuracies for it to be acceptable, and it was filmed in neighboring Malaysia instead.
The real King Rama IV, the King referred to in this movie by his given name of Mongkut, was the great-grandfather of the long-reigning King of Thailand, King Bhumibol Adulyadej, known formally as King Rama IX, who passed away in 2016.
Three months into filming, an outbreak of Japanese encephalitis hampered production. Some sets had to be relocated, as they were too close to pig farms, which were the main source of the outbreak, transmitted by mosquitoes. The entire cast and crew were given a vaccine by the on-set doctor, and some sets were sprayed with insecticide before filming resumed.
During the conversation between Anna and Mongkut after she performed the egg trick, the contents of the glass jars in the classroom stank so much that Jodie Foster and Chow Yun Fat could hardly breathe.
The name given to the wealthy father of Tuptim is actually the name of a famous Thai political scientist. Thak Chaloemtiarana currently directs the Southeast Asia Studies Program at Cornell University.