In ancient Roman religion and myth, Tellus Mater or Terra Mater ("Mother Earth") is a goddess of the earth. Although Tellus and Terra are hardly distinguishable during the Imperial era, Tellus was the name of the original earth goddess in the religious practices of the Republic or earlier.[ The scholar Varro (1st century BC) lists Tellus as one of the di selecti, the twenty principal gods of Rome, and one of the twelve agricultural deities. She is regularly associated with Ceres in rituals pertaining to the earth and agricultural fertility.

The attributes of Tellus were the cornucopia, or bunches of flowers or fruit. She was typically depicted reclining, or rising, waist high, from a hole in the ground. Her male complement was a sky god such as Caelus (Uranus) or a form of Jupiter. Her Greek counterpart is Gaia, and among the Etruscans her name was Cel. Michael Lipka has argued that the Terra Mater who appears during the reign of Augustus is a direct transfer of the Greek Ge Mater into Roman religious practice, while Tellus, whose ancient temple was within Rome's sacred boundary (pomerium), represents the original earth goddess cultivated by the state priests.

The word tellus, telluris is also a Latin common noun for "land, territory; earth," as is terra, "earth, ground". In literary uses, particularly in poetry, it may be ambiguous as to whether the goddess, a personification, or the common noun is meant.

This article preserves the practice of the ancient sources regarding Tellus or Terra.

Hades (/ˈheɪdiːz/; Greek: ᾍδης Hádēs; Ἅιδης Háidēs), in the ancient Greek religion and myth, is the god of the dead and the king of the underworld, with which his name became synonymous. Hades was the eldest son of Cronus and Rhea, although the last son regurgitated by his father. He and his brothers, Zeus and Poseidon, defeated their father's generation of gods, the Titans, and claimed rulership over the cosmos. Hades received the underworld, Zeus the sky, and Poseidon the sea, with the solid earth, long the province of Gaia, available to all three concurrently. Hades was often portrayed with his three-headed guard dog Cerberus.
The Etruscan god Aita and the Roman gods Dis Pater and Orcus were eventually taken as equivalent to Hades and merged into Pluto, a Latinization of Plouton (Greek: Πλούτων, Ploútōn), itself a euphemistic title often given to Hades.