Hyperion (Greek Ὑπερίων, "The High-One") was one of the twelve Titans of Ancient Greece, the sons and daughters of Gaia (the physical incarnation of Earth) and Ouranos (literally meaning 'the Sky'), which were later supplanted by the Olympians. He was the brother of Cronus. He was also the lord of light, and the Titan of the east. He was referred to in early mythological writings as Helios Hyperion (Ἥλιος Ὑπερίων), 'Sun High-one'. But in Homer's Odyssey, Hesiod's Theogony and the Homeric Hymn to Demeter, the Sun is once in each work called Hyperionides (Ὑπεριωνιδής) 'son of Hyperion', and Hesiod certainly imagines Hyperion as a separate being in other writings. In later Ancient Greek literature, Hyperion is always distinguished from Helios; the former was ascribed the characteristics of the 'God of Watchfulness and Wisdom', while the latter became the physical incarnation of the Sun. Hyperion plays virtually no role in Greek culture and little role in mythology, save in lists of the twelve Titans. Later Greeks intellectualized their myths:
Of Hyperion we are told that he was the first to understand, by diligent attention and observation, the movement of both the sun and the moon and the other stars, and the seasons as well, in that they are caused by these bodies, and to make these facts known to others; and that for this reason he was called the father of these bodies, since he had begotten, so to speak, the speculation about them and their nature.
—Diodorus Siculus (5.67.1)
There is little to no reference to Hyperion during the Titanomachy, the epic in which the Olympians battle the ruling Titans, or the Gigantomachy, in which Gaia attempts to avenge the Titans by enlisting the aid of the giants (Γίγαντες) that were imprisoned in Tartarus to facilitate the overthrow of the Olympians.