Factual error: The movie is set in the 1860s. During a performance for English guests, Anna has the King's children perform "Bicycle Built For Two". That song, otherwise known as "Daisy Belle" was written by Harry Dacre in 1892. (00:57:50)
Continuity mistake: When they are riding through the abandoned village, they go past one of the hanged people three times.
Audio problem: At the end of the scene when Anna's wedding ring is thrown in the stream, The Kralahome, Prime Minister, says to King Mongkut "I believe there has been enough insult caused by this woman who believes herself to be the equal of a man." When King Mongkut replies, "Not the equal of a man, the equal of a King," Kralahome is very visibly mouthing his line.
Continuity mistake: When Anna and her son were riding the coach, Louis' hand is visible. He was holding on to something. But when the shot changes angle, his hand is no longer there. (00:04:10)