The world depicted in Terry Pratchett's Discworld series of novels has a lively and complex religious life. The Discworld had numerous gods, all of which clearly exist rather than being socio-cultural inventions. There are also multiple afterlifes, several organised religions and religious orders, and a variety of demons.
The Discworld, being a flat disc supported on the backs of four elephants on top of a giant flying turtle, exists in a region of the universe where reality is somewhat less consistent than it appears in our own, more mundane corner of existence. Because reality on the Disc is so fragile and malleable, belief has a tendency to take on a life of its own, and Gods are far more obvious to the people of the Disc than they appear to us.
Gods are everywhere on the Discworld, a crucial element of the world's peculiar ecology that gives power to belief and demands resolution to any and all narratives. Gods exist in potentia in numbers uncountable, but the moment an event of any note occurs — say, two snails happening to cross at a single point — a god becomes tied to it and begins to manifest in the physical world. Most gods remain small and unknown, but a very few come to the notice of humanity, whose belief then shapes and strengthens them until they gather enough power to join the Disc's vast, unwieldy pantheon.
Gods on the Discworld exist as long as people believe in them and their power grows as their followers increase. This is a philosophy echoing the real-world politics of the power of religion and is most detailed in the novel Small Gods. If people should cease believing in a particular god (say, if the religion becomes more important than faith) the god begins to fade and, eventually, will "die", becoming little more than a faded wispy echo.
The major gods live in an Olympus-like mountain-top kingdom in the centre of the Discworld called Dunmanifestin. They include current king of the gods Blind Io, crocodile-headed Offler, Seven-handed Sek, Fate, The Lady, and Errata, goddess of misunderstandings. Other gods are more local, such as the enormous pantheon of Djelibeybi; Herne the Hunted and Hoki the Jokester of the Ramtops; and the numerous gods of Skund Forest. Trolls also have their own gods.
The Disc also has an almost infinite number of small gods, typically spiritual beings with very little power and no followers. Should they acquire followers, they can evolve into larger gods and gain the ability to manifest themselves and perform miracles.
The main religion on the Disc appears to be polytheism. Most inhabitants seem to believe in all the gods, and to worship whichever seems likeliest to help them. This is shown in Going Postal, when the goddess Anoia suddenly gains a large following after she appears to have granted Moist von Lipwig a large sum of money. However some individuals and families worship the same god for generations, regardless of promises or outcome; for example, the Maccalariat family are said in Going Postal to have been Anoians for generations. Most of the Dunmanifestin gods have their own priests and temples, but no organised religion as such. There are, however, several organised religions on the Disc. Some of these, such as the Young Men's Reformed-Cultists-of-the-Ichor-God-Bel-Shamharoth Association, are mentioned only in passing, but a few are discussed in more detail.
Omnianism is the worship of the Great God Om, and appears to be the Disc's only monotheistic religion. Until about a hundred years before the time of most of the Discworld, it was an intolerant religion known for attempting to forciably convert people and torturing supposed heretics. In Small Gods, Om manifested himself and told his followers to propagate the religion through reasoned argument rather than violence. Omnianism became a simple code of non-violence and moral uprightness, with door-knocking evangelical followers. Because Om encouraged debate, the Omnian church schisms on a regular basis.
The religion of Djelibeybi is essentially a parody of that of ancient Egypt and features god-kings and an enormous pantheon of strange-looking deities with overlapping duties. It is heavily ritualised. In Pyramids, the inhabitants of Djelibeybi had the deeply unpleasant experience of all their gods manifesting themselves.
The Way of Mrs. CosmopoliteEdit
This is a belief system followed by a small number of monks from the Ramtops and is based on the sayings of Mrs. Marietta Cosmopolite, an Ankh-Morpork seamstress. Their koans include 'it never rains but it pours' and 'because'. The Way of Mrs. Cosmopolite is evidence of the phenomenon that wisdom is one of the few things which looks bigger the further away you are from it. The most notable follower of Mrs. Cosmopolite is History Monk Lu-Tze.
Priests and priestessesEdit
Virtually all the successful Discworld deities have priests or priestesses. In the case of minor gods and goddesses such as Anoia, they may share one priest or priestess with several other minor deities, while major gods such as Blind Io have grand temples and a large priesthood. The Discworld clergy are generally portrayed as fat, greedy and prone to bickering amongst themselves. Exceptions include the priests of the Agatean Empire, who are generally poor and beg for a living; and Omnian priests, who were formerly homocidal bigots and are now humble but enthusiastic evangelists. In Ankh-Morpork, the clergy tend to work together when threatened, but will otherwise argue with each other over whose god is the best. The leader of Ankh-Morpork's priesthood is the high priest of Blind Io, Hughnon Ridcully. Priestesses often have priests in their congregation, as this is the easiest way for priests to avoid Mrs Cake.
The history monks organise time and history. They were founded by Wen the Eternally Surprised.
The Balancing MonksEdit
First mentioned in Pyramids as running a free hospital in Ankh-Morpork. The Discworld Companion explains that the Balancing Monks believe the Disc's position on the back of the elephants is precarious, and small weights must be placed in significant positions to stop it tipping over. It is considered they must be correct, since the Disc hasn't tipped over yet. According to Thief of Time they are based in a vertiginous temple criss-crossed with tightropes.
The Monks of CoolEdit
The monastery of the Monks of Cool is found in a laid back valley in the lower Ramtop mountains. They are a reserved and secretive sect and believe that only through ultimate coolness can the universe be comprehended, that black goes with everything, and that chrome will never truly go out of style. To become a fully accepted Monk, a novice is given the following test. Several outfits are laid out in front of him and the tester asks, "Yo, my son, which of these outfits is the most stylish thing to wear?" The correct answer is "Hey, whatever I select." The Monks of Cool have been mentioned in Lords and Ladies and Thief of Time.
The Listening MonksEdit
The Listening Monks are first mentioned in Mort. They believe that, as nothing the Creator made can be destroyed, the echoes of the Word that created the universe must still exist. Their monastery is shaped like an ammonite and built into the exact opposite of an echo valley, funnelling all sound into the main chamber where three monks listen, trying to filter the sound of creation from all the noise of the world. (This could be compared to the real-world study of cosmic background radiation).
A novice is not accepted unless he can tell, through sound alone, if a coin has come up heads or tails. When he has completed his training, he is expected to know what colour it is.
By the time of Soul Music, they have discovered that the sound that brought the universe into being was not a Word, but a musical chord ("the ultimate power chord"). They continue to listen, as they can just make out sound that preceded the creation of the universe, and may put the chord into context. It says in Soul Music that the greatest listeners have determined that the sound before the creation of the universe is "One, two, three, four." and that the greatest listening monk heard a sound before that, going " One, two."
As with the History Monks, the Abbot of the Listeners is continually reincarnated. Unlike the Abbot of the History Monks, however, he does not remember his previous lives (until he dies, when he is in the unfortunate situation of remembering having gone through toilet training several times (50 as of Mort).
The nature of the afterlife on the Disc is very varied, and often depends on what the deceased believed in. Anyone who dies, however, will be met by Death, who takes the form of a living skeleton with a black cowl and a scythe. The only exceptions to this are rats, who are met by the Death of Rats, and anyone who dies during the occasional periods when death is unable to do his job. In theory Death does not collect the souls of everyone who dies, but there is no example in the books of anyone entering the afterlife without seeing Death. Once met by Death, the deceased have been depicted as taking numerous different paths, although in most recent books most of them begin with the Dark Desert.
The Dark DesertEdit
The Dark Desert is a transition phase between life and afterlife on the Discworld. It is described as having brilliantly-lit black sand, under a black sky studded with cold bright stars, stretching away to distant mountains (where judgement awaits). Living people can cross into it, however, it is then harder to come back. Thousands, possibly even millions of people cross it at any one time, though totally unaware of each other, though glimpses may be caught of their movement. It is very important not to fall asleep. Initially, the Dark Desert was the afterlife only for those of the Omnian faith, but it seems to have become the default near-death destination for all those shuffling off their respective mortal coils, Omnian or not.
Several Discworld characters have reincarnated. The Abbots of the History Monks and Listeners both perpetually reincarnate in human form, with each new life becoming the new Abbot. In The Truth, Mr Pin and Mr Tulip are both reincarnated, respectively as a potato and a woodworm.
Halls of the SlainEdit
This is an afterlife which some heroes believe they will go to. It is inhabited by valkyries and bears a strong resemblance to Valhalla (which in fact means "Hall of the Slain"). It is mentioned in The Last Hero, and is referred to, though not by name, in Interesting Times.
In some cases, deceased people do not technically have an afterlife, but an undeath. These include zombies and vampires. Vampirism is traditionally passed on through the bite of another vampire, but as numerous vampire families are depicted in the novels, it seems that it is also heriditary. Zombies are usually made by practioners of voodoo such as Mrs Gogol, but the origin of others, such as Reg Shoe, is unknown, though possibly related to willpower. In Reaper Man, Windle Poons becomes a zombie because Death does not turn up to collect his soul.