The part of the "Queen" was originally cast with Rosalba Neri, but while filming she was replaced by Ángela Rhu. However some footage with Rosalba Neri was left in the film and she can also be seen on many publicity stills.
When Hercules and Maytha first meet, Maytha says how he never saw a white man before, and Hercules remarks about how the Incans are a people he's never heard of before. Despite both of them being totally ignorant of each other's cultures, they speak the same language and have no trouble communicating this to each other.