Theia

In the common Greek genealogical tradition Theia is one of the Titans, born to Uranus (Sky) and Gaia (Earth). By the Titan Hyperion she is mother to Helios (the Sun), Selene (the Moon), and Eos (the Dawn), which locates her in the primeval generation that gives rise to major celestial phenomena. A divergent account reported by Diodorus presents a figure named Basileia (literally 'queen') whose story of royal succession, loss, and visionary instruction leads to the transformation or re-identification of mortal figures as heavenly luminaries and to public veneration; this Diodorean Basileia narrative is noted in the sources as an unorthodox variant and differs significantly from the more standard genealogical accounts.

Surviving texts give no fixed, detailed portrait; instead Theia is evoked through epithets that emphasize brightness and sight (for example Homeric and lyric calls such as 'mild-eyed Euryphaessa' and 'the far-shining one') and through later poetic association with gold and radiance. Some material-culture suggestions exist (a so-called "Theia figure" reported at Cyrene and a debated identification of a goddess near Helios on the Pergamon frieze), but such identifications are fragmentary or conjectural and cannot supply a definitive iconographic type.

Sources primarily ascribe to Theia generative and genealogical functions: she is mother of the chief celestial luminaries and is repeatedly associated with sight, brilliance, and the luminous quality of gold. Classical scholia and poetic passages connect her to the origin of visible splendor (for example, a scholium summarized in the sources states that the Sun came from Theia and Hyperion and that from the Sun came gold). Beyond these associative and maternal roles, texts rarely describe independent acts of power; much of her presence in the tradition is as an ancestral principle and poetic source of radiance rather than as an active agent in a wide range of myths.