A Canticle for Leibowitz is a post-apocalyptic science fiction novel by Walter M. Miller Jr., first published in 1960. It is a reflective work of the Cold War era that explores the cyclical nature of history, particularly the conflict between science and religion. The story spans thousands of years and centers on the monks of the fictional Albertian Order of Leibowitz as they preserve the remnants of humanity's scientific knowledge until the world is again ready for it.