The Chronicles of Narnia she felt were upsetting to children. Poskanzer also noted Lewis presented his Christian message subtly enough as to avoid boring children with overt sermonizing. Examples include: Philip Pullman's fantasy series, "His Dark Materials", is seen as a response to "The Chronicles". Pullman is a self-described atheist who wholly rejects the spiritual themes that permeate "The Chronicles", yet his series nonetheless addresses many of the same issues and introduces some similar character types, including talking animals. In another parallel, the first books in each series – Pullman's "Northern Lights" and "The Lion, the Witch, and the Wardrobe" – both open with
The Chronicles of Narnia and ideas from Greek and Roman mythology as well as from traditional British and Irish fairy tales. The books have profoundly influenced adult and children's fantasy literature since World War II. Lewis's exploration of themes not usually present in children's literature, such as religion, as well as the books' perceived treatment of issues including race and gender, has caused some controversy. Although Lewis originally conceived what would become "The Chronicles of Narnia" in 1939 (the picture of a Faun with parcels in a snowy wood has a history dating to 1914), he did not finish writing the first book "The