The story of "Persephone, Demeter, and Hades" is probably one of the most well-known of Greek myths and is used to explain the coming and going of the seasons.
The myth of Persephone's annual symbolic death and resurrection was the basis of one the largest religious celebrations in ancient Greece, known as the Eleusinian Mysteries. Both Persephone and Demeter were the stars of these celebrations. The Mysteries date to way back in the day and are said to have gone on for about two thousand years.
The Eleusinian Mysteries began as secret ceremonies, but then got pretty mainstream towards the end. Initiates believed that taking part in the rituals guaranteed them a happy afterlife. Eventually, the Mysteries were displaced by Christianity, which has its own story of resurrection and promise of eternal life. (Read more about the Eleusinian Mysteries here.)
The less PG title of this myth is "The Rape of Persephone," which would imply that Persephone's abduction by Hades, lord of the dead, was more terrible than it's sometimes described. Though the myth is very old, it was famously retold by Ovid in his Metamorphoses. Many later European retellings are based on Ovid's version of the tale.
Don't think Persephone has dropped off the face of the map. You see echoes of the myth in the poppiest of pop culture. Persephone is name of a character in the last two Matrix movies. This character is married to The Marovingian, a powerful lord of the underworld. (Hmm, we wonder where they got that idea?) Also recently, Persephone and Hades pop up in the Percy Jackson books and movies.