Tethys was the mother of the three thousand Oceanids and three thousand rivers. There is also a tradition in which she fostered the goddess Hera while Zeus was struggling to overthrow their father Cronus.
Tethys married her brother Oceanus, another one of the original twelve Titans.
Like her husband Oceanus, Tethys embodied the seas, rivers, and oceans of the world.
Tethys, the daughter of Gaia and Uranus, was one of the original twelve Titans of Greek mythology. In later life she married her brother Oceanus and gave birth to innumerable children, including the Oceanids and all the rivers of the world. Despite reproducing so prolifically, Tethys remained an obscure deity; she was not generally worshipped by the Greeks.
The origin of the name “Tethys” (Greek Τηθύς, translit. Tēthýs) remains elusive. In antiquity, the philosopher Plato suggested a fanciful etymology for the name, seeing it as a compound of the Greeks words διαττώμενον (diattṓmenon, “strained”) and ἠθούμενον (ēthoúmenon, “filtered”). Plato claimed that this was appropriate because Tethys was the goddess of springs—which are, indeed, “strained” and “filtered.”1
Unsurprisingly, Plato’s creative etymology has not been accepted by modern scholars. It is possible that Tethys’ name may be connected to the Greek word τήθυον (tḗthyon), which refers to a sea squirt and is in turn likely related to the Proto-Indo-European *dʰeh₁(y)- (“to suck”).2
Other scholars have argued that there is a connection between the Greek Tethys and the Babylonian Tiamat, also a primordial sea goddess. In this case, Tethys was probably originally a Near Eastern goddess who was later imported to Greece.3
Τηθύς (translit. Tēthýs)
Due to her relationship with Oceanus and the aquatic nature of her many children, Tethys was closely associated with bodies of water. In the early stages of Greek religion, Oceanus and Tethys may have been even more important. In Homer’s Iliad, for example, Hera calls Tethys “mother” and says that it is Oceanus “from whom the gods are sprung.”4 These words may have been merely figurative, or they may have represented an alternative cosmogony in which Tethys and Oceanus, not Gaia and Uranus, were the originators of the world.5
According to the Orphics, a religious group that stressed the importance of asceticism and ritual in attaining a blissful afterlife, Oceanus and Tethys were indeed the first divine couple, born a generation before the Titans.6 In traditional Greek religion, however, they were subordinate to Zeus and the Olympians.
In the few sources that mention her, Tethys is consistently portrayed as a maternal figure. In art, she was usually depicted together with her husband Oceanus or other gods, often with small wings growing out of her head.
A daughter of the primordial deities Gaia and Uranus,7 Tethys was one of twelve Titans, the others being Coeus, Crius, Cronus, Hyperion, Iapetus, Thea, Rhea, Themis, Mnemosyne, Phoebe and Oceanus. Tethys’ siblings also included the horrific one-eyed Cyclopes and the equally detested Hecatoncheires—monsters with a hundred hands each.
Tethys took her brother Oceanus as her husband. Together, they gave birth to the rivers of the world as well as the three thousand nymphs known collectively as the Oceanids. Their children were thus too numerous to be named:
there are three thousand neat-ankled daughters of Ocean who are dispersed far and wide, and in every place alike serve the earth and the deep waters, children who are glorious among goddesses. And as many other rivers are there, babbling as they flow, sons of Ocean, whom queenly Tethys bare, but their names it is hard for a mortal man to tell, but people know those by which they severally dwell.8
The Oceanids counted several significant figures among their number: Styx, who represented one of the main rivers of the Underworld; Metis, who mated with Zeus and conceived the goddess Athena; Clymene, a lover of Iapetus; and Pleione, who was the wife of the Titan Atlas and the mother of the Pleiades.
According to an alternative genealogy (which seems to have been associated with the Orphics), Tethys and her brother-husband Oceanus gave birth to all the other Titans (Cronus, Rhea, etc.) as well as the sea god Phorcys.9
Tethys is briefly mentioned in Hesiod’s eighth century Theogony, an epic describing the divine order of the cosmos as the Greeks understood it. Hesiod introduces Tethys as a child of Gaia and Uranus and later elaborates on her relationship with Oceanus and their copious offspring.
For reasons that are unclear, Tethys and Oceanus sided with the Olympians during the Titanomachy, a ten-year conflict between the gods and the Titans. In Homer’s Iliad, Zeus’ wife Hera even claims that Tethys was her foster mother when she was young. In Hera’s words, Oceanus and Tethys “lovingly nursed and cherished me in their halls, when they had taken me from Rhea, what time Zeus, whose voice is borne afar, thrust Cronos down to dwell beneath earth and the unresting sea.”10
Tethys was also sometimes mentioned in connection with Callisto—a lover of Zeus who was transformed into a bear. When Callisto died, she underwent yet another transformation, this time becoming the constellation Ursa Major, the Great Bear. All the other stars, it was said, bathed in the waters of Oceanus as they cycled through the heavens—all except Ursa Major. This was because Hera hated Callisto for having had an affair with her husband Zeus. She therefore asked either Tethys or Oceanus (there are different versions) to forbid Ursa Major from bathing in the waters of Oceanus with the other stars.11
Tethys appeared in 1998’s Hercules and Xena – The Animated Movie: The Battle for Mount Olympus, where she was represented as a water deity with an appetite for destruction. Portrayed as an ardent supporter of the Titans’ cause, the film’s Tethys attempts to kill Aphrodite.
Tethys has also lent her name to one of the many moons orbiting the planet Saturn.
Homer (eighth century BCE): Tethys is mentioned in the Homeric epics as the source of the seas, the rivers, and all life.
Hesiod (eighth/seventh century BCE): In the Theogony, Tethys is named as a Titan and the wife of her brother Oceanus.
Plato (428/427–348/347 BCE): The dialogues Cratylus and Timaeus refer to certain cosmogonies (presumably Orphic) in which Oceanus and Tethys are two of the first beings to come into existence and the origin of all life in the cosmos.
Callimachus (ca. 310–240 BCE): Tethys appears in some of Callimachus’ Hymns. In Hymn 3, for example, Artemis chooses several of Oceanus and Tethys’ daughters to be her handmaidens.
Diodorus of Sicily (ca. 90–30 BCE): The Library of History, a work of universal history covering events from the creation of the cosmos to Diodorus’ own time, contains references to Tethys.
Apollodorus (first century BCE/first few centuries CE): The Library, a mythological handbook, includes references to Tethys.
Orphic Hymns (third century BCE–second century CE): The Orphic Hymns were religious texts produced by the Orphic Mysteries. Tethys features alongside Oceanus in some of these texts, especially the brief Hymn 82.
Nonnus (fifth century CE): Tethys appears a few times in the epic Dionysiaca as a powerful sea deity.
Virgil (70–19 BCE): Oceanus is briefly mentioned in Book 4 of Virgil’s Georgics in connection with the story of Aristaeus.
Ovid (43 BCE–17/18 CE): Tethys plays a minor role in the story of Callisto in Book 2 of the Metamorphoses and is also mentioned in Book 2 of the Fasti.
Hyginus (first few centuries CE): The Astronomica, erroneously attributed to the first-century CE writer Hyginus, mentions Oceanus and Tethys in connection with the myth of Callisto and the constellation Ursa Major. The Fabulae (likewise probably not written by Hyginus) also includes sections on Tethys.
Gantz, Timothy. Early Greek Myth: A Guide to Literary and Artistic Sources. 2 vols. Baltimore, MD: Johns Hopkins University Press, 1996.
Smith, William. “Tethys.” In A Dictionary of Greek and Roman Biography and Mythology. London: Spottiswoode and Company, 1873. Perseus Digital Library. Accessed May 2, 2021. https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0104%3Aalphabetic+letter%3DT%3Aentry+group%3D5%3Aentry%3Dtethys-bio-1.
Theoi Project. “Tethys.” Published online 2000–2017. https://www.theoi.com/Titan/TitanisTethys.html.
Waldner, Katharina. “Tethys.” In Brill’s New Pauly, edited by Hubert Cancik, Helmuth Schneider, Christine F. Salazar, Manfred Landfester, and Francis G. Gentry. Published online 2006. http://dx.doi.org/10.1163/1574-9347_bnp_e1205350.