Dietrich starts from the premises that beliefs and their associated rites are inherently conservative and that, even where populations change, they tend to do so gradually, creating fusions rather than wholesale disruptions in ritual practice. An understanding of classical Greek religion thus, necessarily, depends on appreciation of its forerunners in the Bronze Age; and they, in turn, on evidence from the better documented religions of the Middle East. Dietrich's four main chapters deal first with those eastern links; then with the old traditions of Minoan Crete; next with the interplay of pre-Greek Minoan and Greek Mycenaean cultures; and finally he attempts to bridge the commonly assumed divide between bronze-age and archaic Greece.