There are a few for me. The Lord of the Rings series along with The Children of Hurin gave me a new appreciation of Norse culture, and an interesting new viewpoint on the issue of fate vs. independence. Conn Iggulden’s series on Genghis Khan gave me a new perspective on materialism, as Genghis (my favourite historical character) did not fight for freedom or to gain possessions. He fought for the sake of having an enemy to fight, to keep his people hard and strong, and to bring vengeance on those who tried to make his people weak. Other important ones were The Book of Enoch, Philip Pullman’s His dark Materials series, and Beowulf.
I tend to be readily affected by the arts. Almost every book I read, and almost every movie I watch, as well as many artworks give me a new perspective, new ideas, and a renewed sense of intellectual satisfaction.