During this period peoples’ thoughts, or at least those expressed aloud, were controlled by the Catholic Church and governments in order to maintain the privileged position of the establishment.
Christianity was born in the dark ages, based on the fertility cult, the teachings of Orpheus, Pythagoras and Plato (dominating early Christianity) and Judaism:-
Fertility cults – eg Virgin Mary
Orpheus – Soul’s eternal fate, redemption by actions on earth, man a mix of earthly and divine, church open to all
Pythagoras – Property is common to all, one should prescribe a simple set of rules for all to follow.
Judaism – Chosen people, excludes non-members, restrictive rules, but powerful and effective against oppression
Plato – Utopia, immortality