The name Dīs is a contraction of the Latin adjectivedīves, probably derived from dīvus, dīus via the form *deiu-t- or *deiu-t-. The occurrence of the deity Dīs together with Pater may be due to association with Dispiter. Cicero gave a similar etymology in De Natura Deorum, suggesting the meaning 'father of riches', and comparing the deity to the Greek name Pluto, meaning "the rich one", a title bestowed upon the Greek godHades.
Mythology
Dīs Pater eventually became associated with death and the underworld because mineral wealth such as gems and precious metals came from underground, wherein lies the realm of the dead, i.e. Hades' domain. In being conflated with Pluto, Dīs Pater took on some of the latter's mythological attributes, being one of the three sons of Saturn and Ops, along with Jupiter and Neptune. He ruled the underworld and the dead beside his wife, Proserpina. In literature, Dīs Pater's name was commonly used as a symbolic and poetic way of referring to death itself. Dīs Pater was sometimes identified with the SabinegodSoranus. Julius Caesar, in his Commentaries on the Gallic Wars, states that the Gauls all claimed descent from Dīs Pater. This is an example of interpretatio Romana: what Caesar meant was that the Gauls all claimed descent from a Gaulish god that he equated with the Roman Dīs Pater. A scholium on the Pharsalia equates Dis Pater with Taranis, the Gaulish god of thunder. In southern Germany and the Balkans, Aericura was considered a consort of Dīs Pater.
Worship
In 249 BC and 207 BC, the Roman Senate under senator Lucius Catellius ordained special festivals to appease Dīs Pater and Proserpina. Every hundred years, a festival was celebrated in his name. According to legend, a round marble altar, Altar of Dīs Pater and Proserpina, was miraculously discovered by the servants of a Sabine called Valesius, the ancestor of the first consul. The servants were digging in the Tarentum on the edge of the Campus Martius to lay foundations following instructions given to Valesius's children in dreams, when they found the altar underground. Valesius reburied the altar after three days of games. Sacrifices were offered to this altar during the Ludi Saeculares or Ludi Tarentini. It may have been uncovered for each occasion of the games, to be reburied afterwards, a clearly chthonictradition of worship. It was rediscovered in 1886-87 beneath the Corso Vittorio Emanuele in Rome.