In Greek mythology only Chaos precedes Gaia. Gaia was the Greek goddess of Earth, mother of all life, similar to the Roman Terra Mater (mother Earth) reclining with a cornucopia, or the Andean Pachamama, the Hindu, Prithvi, “the Vast One,” or the Hopi Kokyangwuti, Spider Grandmother, who with Sun god Tawa created Earth and its creatures. 
Gaia was the great mother of all creation--the heavenly gods were descended from her through her union with Ouranos (Uranus) (Sky), the sea-gods from her union with Pontos (Sea), the Gigantes (Giants) from her mating with Tartaros (the Pit), and mortal creatures born directly from her earthy flesh.
Quite simply, Gaia is life. She is all, the very soul of the earth. She is a goddess who, by all accounts, inhabits the planet, offering life and nourishment to all her children.
In the ancient civilizations, she was revered as mother, nurturer and giver of life. It’s she who created and sustained us, and to whom we returned upon death.