Ceres, the ancient Roman goddess of agriculture (identified with Greek Demeter), was patroness particularly of grain, or cereal, and plants. The Latin adjective form is cerealis, «relating to Ceres». She was especially the corn goddess, and, despite her many celestial responsibilities, found time to have a daughter by Jupiter, Proserpine. One day while playing in a field of daffodils, Proserpine was abducted by Pluto, king of Hades, who carried her off to rule as his queen. Ceres was frantic and could not be consoled. She neglected the fruits and grains and all withered and died.
The problem was confounded when a prolonged drought struck. The people prayed to Jupiter, the king of the gods in Roman mythology, for rain, and their prayers were answered. The rains came. Then Jupiter
ordered Pluto to release Proserpine so that she could spend six months of the year with her mother. Ceres was so delighted that she let the grains grow high during Proserpine’s period with her. The people were delighted, too, and they showed their gratitude by building temples in her honor and worshiped her in festivities called Cerealia.
We don’t know whether Kellogg, Post, and the other manufacturers of American cereals pay homage to Ceres, but certainly the American people do as they eat their breakfast cereal.