In Greek mythology Dêmêtêr ( Greek :"mother-earth" ) is the goddess of grain and fertility. She is invoked as the "bringer of seasons " in the Homeric hymns , a subtle sign that she was worshipped long before the Olympian gods and goddesses arrived in the Greek mythos. The Homeric Hymn to Demeter has been dated to sometime around the Seventh Century BC. She and Persephone were central to the long enduring Eleusinian Mysteries that also predated the Olympian pantheon.
The Roman name for Demeter is Ceres , from whom the word "cereal" is derived. According to the Athenian philosopher Isocrates , the great gifts Demeter gave to humanity were cereal and agriculture, and the spiritually transformative Mysteries. At the heart of the Elusinian Mysteries was the myth of Demeter and her daughter Persephone and the life/death/rebirth cycles that were symbolized by her descent into the realm of Hades