Hypnos or Hypnos (Greek: Ὕπνος, transl.: Hypnos, lit. "sleep"), is the god of sleep in Greek mythology. Personification of sleep, and of drowsiness; but not of fatigue as far as fatigue is concerned. Hypnos is one of the Greek daemons: gods who interfere with the spirits of mortals.
According to Hesiod's Theogony, he is the fatherless son of Nix (Νύξ), the goddess of night, but other sources say that his father is Erebo (The Primordial Darkness, which personifies the deep, primitive darkness that formed at the moment of creation).
He has nine brothers, among whom the most important is his twin Tânato, (Θάνατος) the personification of death. So much so that in Sparta, it is common for his image to be placed always next to death, represented by his brother. His other brothers were born only by the will of Nix or the help of Erebo. His Roman equivalent is Somno.
Hypnos lived in a palace built inside a great cave in the far west, where the sun never reached, because no one had a rooster to wake up the world, nor geese or dogs, so Hypnos always lived in tranquility, in peace and silence.
On the other side of all this peculiar place passed Lete, the river of forgetfulness, and on its banks grew plants that, together with the murmur of the clear waters of the river, helped men to sleep. In the middle of the palace there was a beautiful bed, surrounded by black curtains where Hypnos rested, and Morpheus was careful that no one woke him up.
He is usually seen wearing gold garments, as opposed to his twin brother who usually wore silver tones. He may also be depicted as a naked young man with wings, playing his flute. He is sometimes shown as asleep on a feather bed with black curtains around him. His attributes include a horn containing opium, a poppy stalk, a branch dripping water from the river Lete ("Forgetfulness"), and an inverted torch.
Pausanias, in his work Description of Greece, mentions several times the presence of statues of Hypnos next to his brother Thanatus.
Erebo - god of darkness and gloom;
Nix - goddess of the night.
Tânato, god of death;
Ether, god of the sky;
Hesperides, goddess of the afternoon;
Philotes, god of friendship;
Geras, god of old age;
Momo, god of irony and sarcasm;
Oizus, god of misery;
Nemesis, goddess of revenge;
Quer, goddess of man's destiny in his final moments;
Moros, god of the portion that each man will receive in life;
Morpheus - god of good or abstract dreams;
Icelo - god of nightmares;
Phantasus - creator of the inanimate objects monsters, chimeras and daydreams that appear in dreams and remain in the memory;
Fantasia - goddess of delirium and fantasy.
Hypnos gave its name to the psychiatric therapy of hypnosis, and to the treatment of hypnotherapy.
In Masami Kurumada's Knights of the Zodiac series, Hypnos is the name of one of Hades' counselor gods.