In Greek mythology Demeter /də'miː.tɚ/ (Greek: Δημήτηρ, possibly "distribution-mother" from the noun of the Indo-European mother-earth *dheghom *mater, also called simply Δηώ) is the goddess of grain and fertility, the pure nourisher of the youth and the green earth, the health-giving cycle of life and death, and preserver of marriage and the sacred law. She is invoked as the "bringer of seasons" in the Homeric hymn, a subtle sign that she was worshipped long before she was made one of the Olympians. The Homeric Hymn to Demeter has been dated to about the seventh century BC. She and her daughter Persephone were the central figures of the Eleusinian Mysteries that also predated the Olympian pantheon.
http://en.wikipedia.org/wiki/Demeter