Persephone is the daughter of Zeus and Demeter. She is the Goddess of Springtime, Flowers, Vegetation, the Underworld, the Dead, and Wealth. She is the Queen of the Underworld due to her marriage to Hades. Her mother is extremely protective of her and demanded that she spend nine months of the year with her, away from Persephone's husband, lest she loose a famine upon the Earth. In fact, most famines in Earth's history are the result of Demeter punishing the world for Persephone's preference for her husband.
When Persephone was young, her mother hid her away from the rest of Olympus. She kept her daughter all to herself and raised her in nature. When she was of marrying age, many gods asked for her hand in marriage. Though Persephone did not oppose marriage, her mother refused all requests on her behalf and declared that Persephone would remain a virgin goddess at her side for eternity.
This greatly upset Persephone, and she began traveling the world apart from her mother. As she was merely observing nature, Demeter allowed it. On one such trip, she was approached by Hades.
Hades had seen her in the meadows and had fallen deeply in love with her. The two began to meet in secret and, by year's end, she had fallen in love with him as well. Hades approached his Zeus to ask for his blessing to marry Persephone. Though hesitant, when Zeus discovered that his daughter was in love with him, Zeus blessed the union.
The two were married and Persephone departed for the Underworld. At this time, Demeter became aware of her daughter's disappearance but refused to believe that she left of her own volition. She began to punish the earth and swore to continue doing so until Persephone returned.
Persephone and her husband were deeply in love. Persephone, who had only ever been away from her mother for short amounts of time, reveled in the freedom that she had in the Underworld, and she loved her kind and generous husband. Still, though, she missed her mother. She knew that, if she returned to Demeter, her mother would not allow her to leave again. So, she remained.
Finally, Zeus could not ignore the cries of the starving people any longer and demanded that Persephone return to Demeter. Aware that any who ate the food of the Underworld would need to live there forever, Persephone ate a pomegranate to ensure that she would always need to return to her husband.
As such, Persephone lives with her mother for six months of the year. For the remaining six, she lives with her husband in the Underworld. This journey back and forth is the source of the four seasons: Winter is when she is away, Spring when she returns, Summer when she and Demeter are together, and Autumn when her mother grows depressed about her departure.