Most religions have a Pantheon of gods and, even though the Christian religion has the one God, He is often associated with the Trinity, suggesting a mini-pantheon. Only the Jewish faith has a true single god.
Most gods known to Western cultures derive from the Greek/Roman, Scandinavian or Celtic mythologies (> Myths). Prior to the emergence of Genre Fantasy, the Greek gods were the most used in fiction. The Greek pantheon is quite complicated, and though most will recognize Zeus as King of the Gods, he became that only after deposing his father Kronos, king of the Titans. The central Greek pantheon (with their Roman identities where applicable) were Zeus (Jove), Hera (Juno), Aphrodite (Venus), Apollo, Ares (Mars), Artemis (Diana), Athena (Minerva), Demeter (Ceres), Dionysus (Bacchus), Hades (Pluto), Hephaestus (Vulcan), Hermes (Mercurius) and Poseidon (Neptune). There were lesser gods, of whom Eros (Cupid), Helios (Sol) and Pan (Faunus) are best-known. These gods may occur in fiction singly – as in the revival of Aphrodite in The Tinted Venus (1885) by F Anstey and Pan's magical appearance in The Wind in the Willows (1908) by Kenneth Grahame – or in groupings, as in Richard Garnett's The Twilight of the Gods (coll 1888; exp 1903). They also quite commonly appear as a pantheon, especially when the author is lampooning modern society (> Satire): examples are Olympian Nights (coll of linked stories 1902) by John Kendrick Bangs and The Night Life of the Gods (1931) by Thorne Smith. Eden Phillpotts was kinder to the memory of the Greek gods in bucolic sketches including Pan and the Twins (1922), The Miniature (1926) and Arachne (1927). Today they are less utilized, with writers generally favouring the Scandinavian or Celtic gods – except, of course, in the many novels devoted to famous Greek Legends. The most complete series about the Greek gods is the Titans trilogy by Patrick H Adkins.
The Scandinavian Gods are also well known to Western cultures. The main pantheon is the Aesir, under the leadership of Odin (Woden to the Teutons who introduced these gods to England via the Saxons). Their adventures are best known through the Volsunga Saga and the Nibelungenlied (> Nordic Fantasy). J R R Tolkien drew heavily upon this pantheon. (>>> Loki.)
The Celtic Gods have become more prominent with the rise of Celtic Fantasy since the 1970s. While their names, which include Lir, Lugh, Cernunnos and Mabon, are less well known, their adventures have frequently been adapted from the Mabinogion. The Tuatha Dé Danann invaded Ireland and defeated the previous occupants, the Fir Bholg. The Tuatha had magical skills and rapidly established themselves, with their capital at Tara. Their leader, Nuadha, lost his arm in battle with the Fir Bholg and was fitted with a silver one, becoming called Nuadha Airgedlámh (of the Silver Hand). He later abdicated in favour of Lugh. The Tuatha were eventually defeated by the Milesians, the first true Gaelic Irish, who later worshipped the Tuatha as gods. The Tuatha goddess Ériu gave her name to Ireland, as Eire, because she proclaimed the Milesians would inherit the land. (> Morgan Llywelyn, Paul Hazel, Keith Taylor and particularly Kenneth C Flint for relevant works.)
Other gods who sometimes appear in fiction include: the Egyptian pantheon – Re (or Ra), Isis, Osiris, Horus and Thoth; the Hindu Pantheon – Brahma, Siva and Vishnu; Quetzalcoatl, from the Aztec pantheon; Enlil, the Sumerian god of the air; Marduk, the chief Babylonian deity; Ashtoreth, the Philistine Fertility goddess based on the Sumerian Ishtar (> Goddess); and the Phoenician Baal and Dagon. As understandings of past cultures develop, so their gods are borrowed more meaningfully into fiction. Roger Zelazny adapted the Hindu pantheon in Lord of Light (1967) and deployed the Egyptian gods in Creatures of Light and Darkness (1969). Carlos Fuentes has drawn upon the Aztec gods, while Chinese and Japanese gods frequent much Oriental Fantasy.
As the older gods gave way to Christianity, so the old-world Magic began to fade (> Thinning). This passing is explored best in the works of Thomas Burnett Swann. That the old gods might still be re-awakened is a theme increasingly popular in stories of white magic, particularly in Nature myths (>>> Algernon Blackwood; Charles de Lint; Robert Holdstock). The old gods may also be summoned for Black Magic, and many stories of the occult rely on worship of the Elder Gods (>>> Aleister Crowley; Arthur Machen; Dennis Wheatley).
Any genuine Secondary World or autonomous Otherworld requires its own Religion and thus its own gods. Lord Dunsany realized this from the outset with The Gods of Pegana (coll 1905). E R Eddison created a complex theogony in his Zimiamvia series, with gods and men indistinguishable other than through their world-making abilities. J R R Tolkien went furthest in the creation of a complex pantheon of gods for Middle-Earth. Other writers who have treated gods seriously are L Sprague de Camp, Philip José Farmer, Michael Moorcock, Terry Pratchett, Michael Shea, Jack Vance and Roger Zelazny. H P Lovecraft is unusual in creating a pantheon within our own world (> Cthulhu Mythos).
In anthropomorphic fiction, animals have their own gods, which may be based on the human world. Richard Adams created a rabbit mythology in Watership Down (1972).
The interaction between gods and humans can at times become intense. In the finale of Stephen Donaldson's White Gold Wielder (1983) Covenant realizes he must transcend into a godlike state in order to defeat Lord Foul. Conversely, gods may become human to understand the human condition. A E van Vogt explores this on a vast timescale in The Book of Ptath (1947). [MA]
further reading: The Encyclopedia of Gods (1992) by Michael Jordan.