The Chronicles of Narnia is a series of seven fantasy novels for children written by C. S. Lewis. It is considered a classic of children's literature and is the author's best-known work, having sold over 100 million copies in 47 languages. The series borrows characters and ideas from Classical, Norse, Irish, Arthurian, Islamic, Jewish and Christian mythology. Of all the mythologies taken into consideration, the Christian one is the most fundamental for the Narnia series, due to the themes covered.