Book excerpt: Seers, Shrines and Sirens (1965) surveys the history of Greek religion during the great formative and revolutionary era of the sixth century BC. It treats, among other subjects, the rise to prominence of the Delphic oracle, the growth of religious festivals and mysteries, the worship of Dionysus, including the development of the drama and appearance of the Orphic and Pythagorean sects. The sixth century was above all a time when prophets, supermen and sibyls flourished and their impact is discussed in detail.