In modern times, we know what causes seasons. For the Ancient Greeks, their explanations for seasons was drastically different. It stemmed from a tale about Persephone, the daughter of the harvest goddess, Demeter, and her meeting with Hades, god of the underworld.
Hades had decided to take a trip out of his normal abode and, with Cerberus in his chariot, he flew up to Earth and eventually spotted Persephone. While many recoiled at the sight of the three-headed dog, Persephone was merely intrigued by the animal. Hades, having spent countless years relegated to the underworld, was amazed not only be the interaction, but also by Persephone’s beauty. He wanted to take her as a wife and, with nobody around to stop him, he took Persephone back with him to the underworld.
Once they were back, Hades tried countless times to make Persephone eat any of the food there, in the knowledge that if she did, she would have to stay with him below the Earth. While she tried to fight off hunger, she eventually gave in and ate 6 pomegranate seeds. While it was barely enough to even begin to satisfy her hunger, she had now bound herself to Hades and his domain and she burst into tears.
While she was upset, her mother was distraught. Demeter, as the goddess of the harvest, had to ensure that the crops grew to allow the humans to survive, but she had lost all interest in her duties. She yearned for her daughter, but saw no solution.
Zeus intervened in an attempt to restore order to the human world by sending Hermes to negotiate the release of Persephone, but they eventually decided that she would have to stay in the underworld for half of every year, 1 month for every seed she ate. When she was away from Demeter, the crops would wither and die for Winter, but they would flourish once more when she returned in Spring.