Persphone grew up a happy child on Olympus. Her mother was Demeter, the goddess of harvest. Peresphone was so lovely everyone wanted to be with her - even Hades...
Hades wanted Persephone for his queen so he cracked open the earth and took her down to the Underworld with his chariot and horses. Only a pig herder saw the whole thing happen.
Hades seated Persephone as his queen... but she was miserable. She even refused to eat from the only fruit bearing tree in the Underworld, a pomegranate tree.
Without Persephone, Demeter was crushed and nothing grew for months. The world was cold and bitter. No crops or plants grew, so Zeus sent Hades down to Hermes to tell him to let Persphone go.
By the time Persephone was let go, she had realized she ate some of the pomegranate seeds. Zeus ruled that he would allow Persephone to live above ground for half of the year only. For the other half, she had to live in the Underworld.
From then on, every year Persephone would spend half of the year with her mother Demeter, and half of the year with her husband Hades. When she was with her mother, nature would bloom in spring and summer. When she left, the earth would be cold and barren in fall and winter.