Pluto

Pluto (Greek Plouton) is a deliberately propitiatory name for the ruler of the dead, connected with ploutos, wealth, the riches of metals and, above all, the grain that springs from beneath the ground. Greeks were reluctant to name Hades directly, and Plouton let them address the god of the underworld as a giver rather than only a terror. The name rose to prominence through the Eleusinian Mysteries, where the lord of the dead appeared not as an abductor but as a solemn consort of Persephone and a source of the earth's abundance, sometimes shown holding a cornucopia. This is the positive face of the underworld god, and it is the reason a deity of death carries a name meaning wealth.

Pluto is regularly shown in later Greek and Roman art holding a large key as well as the cornucopia, the key that locks the gates of the dead and ensures none return without his leave, a darker attribute balancing the abundance suggested by the horn of plenty. A handful of actual cult sites called Ploutonia, sanctuaries built around openings believed to lead to the underworld, are known archaeologically, the most famous at Hierapolis in Asia Minor, where the geographer Strabo describes a cave that killed any animal driven into it by toxic vapour, a site excavated and confirmed in 2013 to emit lethal volcanic carbon dioxide; ancient priests of Cybele reportedly entered and survived, an effect modern researchers attribute to holding their breath rather than divine favour.

At Rome the same god was worshipped as Dis Pater, a direct Latin translation, dis being a contraction of dives, rich, and identified with an older Italic death-god, Orcus, whose name survives in Italian orco and, at a distance, in the English ogre. In 249 BCE the Romans instituted nocturnal sacrifices to Dis Pater and Proserpina at an altar in the Campus Martius as part of the games later known as the Secular Games. The name found a modern afterlife in 1930 when the newly discovered ninth planet was named Pluto, a choice that pleased its backers partly because its first two letters were the initials of Percival Lowell, so that the Roman lord of the hidden depths gave his name to the most distant and shadowed body then known.

Medieval readers frequently blurred Pluto with a distinct Greek deity of similar name, Plutus, the personified god of wealth and abundance who appears in Aristophanes and Hesiod; Dante's Inferno places a demon called Pluto, drawn from Plutus, guarding the fourth circle of the avaricious and the wasteful, a conflation later scholars have traced to the two names' near-identity in Latin translation and to Pluto's own ancient reputation, sketched already at Eleusis, as a giver of the earth's riches rather than merely their lord below. The confusion persisted into Renaissance mythography before philologists began to separate the two figures more carefully.