The most influential and popular of all the Greek mystery cults were those of the goddess Demeter and her daughter Kore (Persephone) at Eleusis. Eleusis was an important town in Attica, about 21 km north-west of Athens.
It was believed from the most ancient times in Greek history that it was Eleusis that the gods had given mankind the gift of agriculture, in particular grain. Because of this an early agricultural cult grew at Eleusis which commemorated the yearly sowing of the grain in the Greek month of Boedromion (September/October). Like this early agricultural cult the Eleusinian mysteries celebrated fertility and life.
Before Athens took control of Eleusis (shortly before 600 BC), the mysteries of Demeter and Kore were conducted by an independent Eleusis. After Athens assumed jurisdiction of the mysteries, however, Athenian interests naturally predominated in the celebration of the Eleusinian mysteries from this point.
The mysteries at Eleusis focused upon the goddesses Demeter and Kore. Demeter is probably a Cretan goddess by origin (as she is in the Homeric Hymn) and is most likely the “Grain Mother” by name, though some scholars suggest her name means “Earth Mother”. Kore is the “Maiden”, and because of her kidnapping by Hades into the realm of the dead, she is often identified with the figure of Persephone, queen of the underworld. Both Demeter and Kore are personifications of grain: Demeter is the mature grain with maternal potency while Kore is the newly planted grain.
Our information of the specific features of the mysteries (secrets highly guarded in antiquity) derive mainly from the era of Athenian domination of the mysteries not before. It was during the month of Anthesterion (February) that the lesser mysteries took place near Athens, at Agrai by the Ilissos River, as something of a preparation for the greater mysteries.
The greater mysteries took place in the month of Boedromion (September/October). Using a variety of sources we can reconstruct the celebration.
On the 13th day of Boedromion, Athenian youths carried kistai (chests) and ta hiera (“sacred things” what these were remains a mystery to this day) from Eleusis to Athens where they were temporarily stored in the Eleusinion, the Eleusinian temple, in Athens.
On subsequent days a herald in Athens would exclude criminals and barboroi (those who didn’t speak Greek) from the mysteries. All those participating in the mysteries would go down and bathe in the sea. They would feast, they sacrificed young pigs to the goddesses and they put on ritual garments.
On the 19th day of Boedromion, there was a great procession along the Sacred Way from Athens to Eleusis called the Iacchos procession. They carried the “sacred things” back to the goddesses, they sang and danced along the root, and carried torches all the way to the Telesterion, the great hall of initation, at Eleusis.
What happened next remains one of the greatest secrets of the ancient world. Simply put we don’t know for certain. We know sacred things were spoken, performed and shown but we don’t know what these were. Later Christian writers wrote that these rites were sexual in nature however their testimonies must be treated with considerable caution.
The mythic tradition of the mysteries comes from the Homeric Hymn to Demeter. It recounts the raope of Persephone and Demeter’s quest to retrieve her daughter; after which the foundation of the Mysteries at Eleusis is described.
The mysteries appear to have had a strong link with the underworld and achieving a better lot for oneself in the afterlife. One line of the hymn states:
“she showed the tendance of the holy things and explicated the rites to them all…sacred rites, which is the forbidden to transgress, to inquire into, or to speak about, for great reverence of the gods constrains their voice. Blessed earthbound men is he who has seen these things, but he who dies without fulfilling the holy things, and he who is without share of them, has no claim ever on such blessings, even when departed down to the mouldy darkness.”
In Aristophanes play Frogs initiates of the mysteries are shown in the underword celebrating the mysteries in death as they would have done in life. They are described as robed in white hold torches, singing and dancing. They are also feasting on the meat of sacrificed pigs. Demeter is described as the goddess of Salvation who allows her initiates to enjoy their afterlife as a never ending celebration of joy.
According to the Roman Cicero (Laws, II.xiv.36)
For among the many excellent and indeed divine institutions which your Athens has brought forth and contributed to human life, none, in my opinion, is better than those mysteries. For by their means we have been brought out of our barbarous and savage mode of life and educated and refined to a state of civilization; and as the rites are called “initiations,” so in very truth we have learned from them the beginnings of life, and have gained the power not only to live happily, but also to die with a better hope.
The mysteries were one of the last pagan cults to end after the advent of Christianity in the 4th century AD.