 Darryl F. Zanuck (qv) first cast Maureen OHara (qv) as "Anna"  because she was not only gorgeous but had a fine soprano voice and  would not have to be dubbed. When Zanuck told her the news, she  immediately sent sample recordings of her voice.  Richard Rodgers (I) (qv) agreed that OHara had a great voice but  reportedly said, "No pirate queen is going to play my Anna!"