Over 100 actors auditioned for the voice of Reepicheep before Eddie Izzard was cast. He based his performance on Errol Flynn.Anna Popplewell had to absent herself from several days filming to complete her school exams.
Anna Popplewell was disappointed that Susan didn't get to use her bow much in the first film. Which is why she uses it so often in this one.
A romantic subplot between Anna Popplewell's character and Ben Barnes' Prince Caspian was in an early draft of the script but was mostly dropped. In the book they don't even meet until the very end of the story.