At the ball, Emily removes her right glove in order to take the canapé from the serving tray. Moments later, as she greets Poppy, her right glove is fully back on to her hand.
Emily calls her friend in Philadelphia after waking up in the morning in Europe. Her friend is wide awake and it is quite light in Philadelphia where it should still be dark.
When Leo, Natasha and Queen Isadora leave Emily to ride horses for the day, Emily is seen wearing a jacket. When she walks inside, it's gone.
When Bud Taylor asks Leo to sign the photograph he has already taken out the yellow pen from his coat. However he reaches inside a different jacket pocket and retrieves the same pen for Leo to use.
When the first dinner is served the "jellied eels" are actually the tentacles of either octopus or squid. You can see the suckers which eels do not have.
When Prince Leopold and Emily go out to the village, the prince tells the estate motor man that he will drive. The vehicles are British Range Rover SUVs but are left hand drives. In the area of of Europe that Prince Leopold lives, automobiles would be right hand drives.
At the end of the movie when Emily is sewing, she has the thimble on her left index finger when it should be on the right index finger.
The queen states that Benjamin Franklin wasn't the first to discover electricity, it was discovered by an "English man" however Franklin was an English man.
The orchestra that plays during the Christmas ball scene is primarily made up of strings. However, what is heard is played by a full orchestra (drums, woodwinds, etc.).
During the ball preparations Victor tells Emily to only curtsy if it's a princess but during the ball she curtsies to the Baron and Baroness of Newbury, who are ranked lower.
During the ball, Emily calls Leo 'Your Majesty', instead of 'Your Royal Highness'.