Goddess sita was the wife of lord shri ram and central woman character in Ramayan . She was considered a female deity of agricultural fertility . She was born in Sitamarhi (Punaura) in Bihar (India), Sita was discovered in a furrow when Janaka was ploughing. Hence Sita is also said to be the daughter of the Mother Earth (Bhoomidevi) So, Devi Sita is a personification of the Earth`s fertility, abundance, peace and prosperity.
Sita was taken to Janakpur (Kingdom of Janak )(in the present day Nepal) soon after her birth. Sita is also considered an incarnation avatar of wealth goddess Lakshmi, consort of Shri Vishnu .
She is personification of womanhood. In Rigveda she is considered the Earth Goddess who blesses the land with fertile soil and good crops.
King Janaka realizes that Sita has come of marriageable age , he arranged a Swayamwara to find out suitable brave and polite husband to her loving daughter . he invited most of brave kings in this grand occasion . King janaka welcomed all coming kings of different states and declared that he would marry her daughter to that king who would life the vow of lord shiva and string it . almost every king had failed to do so then lord shri ram easily lift it and awarded with her marriage .
When goddess sita knew that her children have been united with their father , sita thought her mission of life was now complete. She didn’t wish to return to ayodhya and prayed to her mother earth to take her back in her lap. She want to release this world now. The mother earth splits and welcome her.