Hades is one of the three masters who divided among themselves the command of the universe after the victory over the Titans. While Zeus obtained the Heaven and Poseidon the sea, he was attributed to the underworld, or Tartarus, where he reigned over the dead. He is a pitiless master, who does not allow any of his subjects to return among the living; detested by gods and feared by men, he is assisted by demons of different origins, that are placed under his orders (e.g. the ferryman Charon, etc...). His name, meaning "the Invisible" was not usually pronounced because they feared, when calling him, to excite his anger. So he was designated with euphemisms, the most common of which was Pluto (the "Rich"), alluding to the inexhaustible richness of the earth, both the cultivated land, and the mines that it conceals. So Pluto is often depicted as holding a horn of plenty , a symbol of that wealth.
Next to him reigns Persephone (Proserpine for the Romans), no less cruel and inflexible with her subjects; she had been abducted by the god one day when she was with her companions picking flowers in the plains of Sicily.
Demeter (the Roman Ceres, goddess of the harvest), mother of Persephone, in the long wandering in search of her daughter had ignored the earth, causing its drying, and had upset the world order, but eventually she obtained from Zeus the order to Hades to return Persephone. But Hades had taken his precautions, forcing the girl to eat a grain of pomegranate: now that she had visited the Empire of the dead, and had dined here for something, she would not be able to go back to the residence of alive. So Demeter had to reach a compromise: Persephone would divide the year between the underworld and her mother. So each spring Persephone flees from the underground when the first shoots sprout from the furrows, but returns again in the shadows at the time of sowing, and the soil remains sterile as long as she remains separated from Demeter in the season of sad winter.
The name Hades also generically designated the underworld, just as Avernus for the Romans stood for "the dead". Hades-Pluto is depicted, in ancient art, with dark characters in the face, bearded, dressed in a tunic and a heavy cloak; his characteristic attribute is the dog Cerberus, triceps. In Etruscan tomb paintings he has a wolf-skin on the head.
The topography of the kingdom of the underworld is quite complex and varied, starting with its doors, that, according to legends and traditions, are now in the lands of the Cimmerians, now in the Campania region near Lake Avernus, now in Sicily, now in Arcadia. To it belongs also the Elysium (the Elysian Fields of Virgil) as otherworldly house for the elect, while the Tartarus is reserved to the wicked as a place of punishment. The Elysium is located, by Homer, at the end of the world, and by Hesiod, with the name of the Islands of the Blessed, near the ocean currents; this because it is the seat of God Ocean , who generated with his wife Tethys all the waters and hence the four rivers that flow in the underworld: Acheron, Cocytus, Styx and Phlegethon.
Acheron is the ancient name of many rivers, the best known, however, was the one in Tesprotys in Epirus, flowing partly underground, which forms the swamp Acherusia near the sea; that's why it was believed to be the entrance to the underworld and became the main river of Hades, named for the first time in the Odyssey; the souls could go over it only if their bodies were buried; they were ferried by the boatman Charon, to whom they had to pay a sum for the transportation, that's why in the burial it was normal to put a dime in the mouth of the dead man. In the Latin world the name Acheron usually indicates the underworld.
Cocytus is another of the infernal rivers; already mentioned by Homer, are immersed in it, as described by Plato in the Phaedo, the common sinners. (in Dante's Inferno the Cocytus is the confluence of all rivers and forms the infernal "frozen lake" in last "circle", the one of traitors).
The Phlegethon (in greek "burning"), sometimes also called Piriphlegethon in greek-roman mythology joins the Cocytus to form the Acheron. From its flames, according to the myth exposed in Plato's Phaedo, derives the volcanic lava. The mythographers and poets imagined that in it were punished parricides, bandits and tyrants.
Styx in Homer and Hesiod is the river of the underworld by excellence and appears as the "water of Styx", the latter being considered a goddess of hell (one of the Oceanids , daughter of Teti the Titanide, or daughter of Night and Erebus); its water had magical properties and in this river Thetis the Nereid dipped the child Achilles to make him invulnerable; on the water of the Styx swore the gods, suffering terrible punishments if they had not complied with the oath. The effects of perjury are inferred from a passage of the Theogony, which provides more details on the nature of this fatal water: it is an arm of the ocean, equivalent to one tenth of the original river, and forms with the other nine rivers the nine coils that envelop the disk of the earth. This figure of the nine turns is found in Virgil's description of the hellish Styx, that surrounds the kingdom of the underworld with its maze. Odyssey's Styx is more clearly defined as a river; in later traditions, the figure of the goddess tends to disappear and comes back a very ancient tradition (already present in Homer) that derives from the river Styx many other rivers, or identifies it in watercourses or swamps, besides which was the entrance to the underworld.
The name of Ceres was given to one of the satellites of Jupiter by Gio Domenico Cassini , born in Perinaldo (Imperia) in 1625 and then called by Colbert to improve and direct the Observatory of Paris, where the scientist died in 1712.