Demeter

Demeter, in Greek religion, daughter of the deities Cronus and Rhea, sister and consort of Zeus (the king of the gods), and goddess of agriculture. Her name indicates that she is a mother.
Demeter is rarely mentioned by Homer, nor is she included among the Olympian gods, but the roots of her legend are probably ancient. The legend centres on the story of her daughter Persephone, who is carried off by Hades, the god of the underworld. Demeter goes in search of Persephone and, during her journey, reveals her secret rites to the people of Eleusis, who had hospitably received her (see Eleusinian Mysteries). Her distress at her daughter’s disappearance was said to have diverted her attention from the harvest and caused a famine. In addition to Zeus, Demeter had a lover, Iasion (a Cretan), to whom she bore Plutus (Wealth; i.e., abundant produce of the soil).
Demeter appeared most commonly as a grain goddess. The name Ioulo (from ioulos, “grain sheaf”) has been regarded as identifying her with the sheaf and as proving that the cult of Demeter originated in the worship of the grain mother. The influence of Demeter, however, was not limited to grain but extended to vegetation generally and to all the fruits of the earth, except the bean (the latter being the province of the hero Cyamites).
Demeter also appeared as a goddess of health, birth, and marriage. A certain number of political and ethnic titles were assigned to her, the most important being Amphiktyonis, as patron goddess of the Amphictyonic League, subsequently well known in connection with the temple at Delphi.
Her attributes were connected chiefly with her character as goddess of agriculture and vegetation—ears of grain, the mystic basket filled with flowers, grain, and fruit of all kinds. The pig was her favourite animal, and as a chthonian (underworld) deity she was accompanied by a snake.

Source: (https://www.britannica.com/topic/Demeter)