God, place, or both
Theoi's Erebos page defines Erebus as the protogenos of darkness and the consort of Nyx. His dark mists encircled the world and filled the deep hollows of the earth (Theoi: Erebos).
Theoi adds that the name Erebos was also used as a synonym for the netherworld realm of Haides. That double use is the main modern confusion: writers say "sent to Erebus" meaning the underworld, without naming the primordial person.
In the ancient cosmogonies Theoi summarizes, heavenly Aether and the dark mists of Erebus were treated as sources of day and light cycles rather than the sun alone. Darkness here is a cosmic material, not only a moral metaphor.
Hesiod's lineage
In Hesiod's Theogony, as Theoi cites, Erebus comes from Chaos, then with Nyx fathers Aether and Hemera. That is the short genealogical answer most survey courses want.
Later mythographers expand the children. Hyginus's preface, quoted on Theoi, attaches a long list of personified forces to Nyx and Erebus together: Fate, Old Age, Death, Sleep, Dreams, Strife and others. Those lists are encyclopedic, not a single Hesiodic household roster.
Orphic material on Theoi gives an alternate parentage from Khronos and Ananke. Flag the tradition when you cite it; do not blend Orphic parents into a Hesiod-only paragraph.
Erebus vs Hades vs Thanatos
Hades (Pluto in Latin contexts) is the Olympian-generation ruler of the dead and the name of his realm. Erebus is older: darkness as a first being, and a word for the dark mist of that realm. For the ruler comparison, see Hades vs Pluto.
Thanatos is Death as a daimon, often listed among Nyx's children. He is not interchangeable with Erebus. Saying "god of death" when you mean primordial darkness, or the reverse, collapses three different entries.
Charon ferries the dead; he is a functionary of the underworld, not a cosmogonic darkness. See Charon in Greek mythology.
How to use the name in a sentence
If you mean the personified god, capitalize and pair him with Nyx or Chaos. If you mean the gloomy region souls pass through, say so explicitly ("the gloom of Erebus") so readers do not hunt for a cult statue that never existed.
Homeric poetry already uses erebos as a dark underworld word. That poetic usage is older than modern encyclopedia splits, which is why careful notes keep both senses on the table.
Reading Theogony lines on darkness
Hesiod's Theogony opens with Chaos, then broad Earth (Gaia), and dim Tartarus in the depths, with Eros also among the first. Erebos and black Night (Nyx) are born from Chaos in the genealogy that follows. From Night and Erebos come Aether and Day (Hemera) in the usual teaching extract.
That sequence makes Erebos a primordial personification of darkness rather than an Olympian with temples and civic cult. Open the Perseus Evelyn-White English Theogony (and the Greek if you can) and you can verify the parentage without relying on a single aggregator page.
Later poetry sometimes uses "Erebos" as a place-word for the dark underworld region souls pass through. The double life (god name and place name) is normal for Greek cosmic vocabulary; context decides which sense is live.
Cult, imagery, and later reception
Erebos does not attract the same vase-painting celebrity as Zeus or Athena. Artists rarely need a distinct iconographic kit for cosmic darkness the way they need thunderbolts or owls. Most students meet Erebos in genealogy charts and in underworld geography notes.
Roman and later English poetry keep "Erebus" as a lofty synonym for hellish dark. That literary afterlife can trick readers into equating Erebos with Hades the god or with Thanatos. Hesiodic taxonomy says otherwise: Hades rules the underworld realm; Thanatos is Death as a daimon; Erebos is primordial dark (and sometimes the dark zone itself).
When a modern fantasy page lists "Erebus, god of shadows" beside a cast of personality-heavy deities, check whether it is paraphrasing Hesiod or inventing a comic-book portfolio.
Pairings: Nyx, Aether, Hemera
Night (Nyx) is Erebos's partner in the Theogony stemma that produces Aether and Day. The pairing is cosmological: darkness and night yield the bright upper air and day. It is not a soap-opera marriage narrative with episodes.
Aether here means the bright upper sky, not the chemical anesthetic. Hemera is Day as a goddess/personification. Together they complete a day-night circuit that Hesiod encodes as birth relations.
If your course packet only says "Erebus = darkness," add one sentence on Nyx and one on the Aether/Hemera children so the name sits inside Hesiod's system instead of a flat glossary synonym.
Sentence tests for writers
Good: "In Hesiod, Erebos and Nyx come from Chaos, and their children include Aether and Hemera." That is genealogy.
Good: "Odyssean and tragic language can send someone into Erebos as a dark region." That is place-sense.
Risky: "Erebus judges the dead." That job belongs to underworld rulers and related figures, not to the primordial dark in Hesiod's opening catalog.
Risky: "Erebus is just another name for Hades." Sometimes poets blur underworld words in atmosphere, but study notes should keep the labels separated unless a specific passage equates them.
For MythCairn internal links, pair this page with other primordial or underworld explainers rather than late Olympian cult tours.
Underworld vocabulary map
Hades can mean the god or his realm. Tartarus in Hesiod is a deep cosmic pit, later also a dungeon for the damned in broader tradition. Erebos shades toward primordial dark and the gloomy approaches of the underworld in poetic usage.
Thanatos and Hypnos (Death and Sleep) are Night's children in Theogony catalogs that students often meet beside Erebos, but they are agents, not darkness itself. Charon ferries; judges judge; Erebos does not run a ferry schedule.
A clean study card has four rows: Erebos (dark/protogenos), Nyx (Night), Hades (ruler/realm), Thanatos (Death). Mixing those rows is the most common textbook error this page is meant to prevent.
When you quote Hesiod, link a stable text (Perseus Evelyn-White) so a reader can see Chaos producing Erebos and Nyx without trusting a single secondary paraphrase.