Interfaith Smoothie

This is when a constructed fictional religion is clearly a mix of any number of real-world religions. An author will often use this by combining various interesting bits of existing religions, belief systems, and philosophies, and changing the names and places to make the new religion fictional.

Differs from Crossover Cosmology in that this creates a 'new' cosmology from pieces of established idea systems. Popular in Space Opera and Science Fiction as representative of alien cultures. A subtrope of Ninja Pirate Zombie Robot. Can also be Truth in Television since there are few religions that don't share certain rituals or beliefs with other religions.

Examples of Interfaith Smoothie include:

Anime and Manga

• This seems to come up a lot in Anime fantasy settings, though it could (and oftentimes appears to) just be a cultural misunderstanding of Western ideas and philosophies while substituting familiar concepts (like Buddhism and Shintoism) into the knowledge gaps.
  • Also, sometimes in Anime, instead of All Christianity Being Catholic, you'll see a mix-mash of ideas from various Christian denominations all pooled into a single faith. This probably has a lot more to do with the aforementioned Critical Research Failure, though.

Comic Books

• In "Tintin in America". It's a mixture of Judaism, Buddhism and Islam, they claim they were the fastest growing religion, and want Tintin to become a member of them.

Film

• The Force, once described by Mark Hamill as "Religion's Greatest Hits!" The religion of the Force has strong elements of Buddhism, Jainism, Hinduism, Daoism and a bunch of other mystical traditions, with Christian symbology (the Jedi are Knights In Brown Robes and not for nothing is the hero named Luke).

Literature

• The Thursday Next series has the Global Standard Deity, a church that openly and shamelessly mixes and matches elements of various faiths.
• The end of the Pendragon series has Ravinia, in which people see life in the rest of the universe (Halla) for the first time. This is not a religion in itself, but something that attracts people regardless of religion into one group. On the other hand, it divides people based on social class.
• The far future religions in the Dune series are either this or the Coca Pepsi Inc type. The Coca Pepsi Inc ones are the more numerous though.
• The Videssos books, being chockablock with Fantasy Counterpart Cultures, have lots of these. The religion of Videssos proper (the fantasy analogue of the Byzantine Empire) looks a lot like Orthodox Christianity (with bishops, monks, ecumenical councils, schisms over variations in the Creed), but the dualistic belief system is much more like Zoroastrianism (two powerful gods, one good and one evil, at war). There are heresies with variant understandings of the war (Videssians believe the good god is sure to win, Khatrishers believe the two gods are perfectly balanced, Namdaleni believe the gods are balanced but you ought to act as if you're sure the good god will win). The main other empire starts out as practically-Muslim (with belief in a single God and four supreme Prophets), but ends up being dominated by a diabolist religion that worships the evil Videssian god.
• In Life of Pi, the title character manages to be a practicing Hindu, Christian, and Muslim all at once, to the confusion of most of the other characters.

Live Action TV

• The Klingon belief system seems to be an odd mish-mash of Shinto and Norse mythology, with a Messianic Archetype figure (Kahless) thrown in. Vulcan spirituality seems to have elements of Shinto ancestor worship within a predominant Buddhist philosophy, with 'logic' substituted for Dharma. The Bajoran faith which features prominently in nearly every episode of Star Trek Deep Space Nine may be the ultimate example of this trope, combining elements of all three Western monotheisms (Judaism, Christianity and Islam) together with Eastern Hindu/Buddhist mysticism.
• Wayism in Andromeda was this. It was mostly Buddhist 'peace in suffering' teachings, with a few other things thrown in. In-universe it was created by a Magog who was taught the concepts of various religions to him by the human host he was spawned from.

Video Games

• Solatorobo's Oshilasama seems to be one part the Buddhist-Shinto amalgam common to Japan and one part Functional Magic. Oh, and something about an evil dog-god who loses his powers if you turn his statues upside-down.
• Oracle of Tao has a strange mix of Shintoism, Taoism, and Christianity. They call it Aiken (based on Japanese ai ken, not Clay Aiken). It's basically very heavily into nature and love (and ancestor worship).
• In EV Nova, the Church of Krim-Hwa is this in-universe.
• In Fallout: New Vegas DLC Honest Hearts have one of three Tribes, The Sorrows then recently now believing a new version of their old Tribal religion which based of their ancestors Guardian "The Man in the Cave" with Mormon's version of Christianity (especially in their Creation myth) due of Mormon missionary Daniel tries to convert them to Mormonism but comes out as both half successful and half failed instead.

Web Comics

• The Church of Slag-Blah in Buck Godot: Zap Gun for Hire who are "militant agnostics" and celebrate a different religious holy day every day.
• In an Xkcd strip, this discussion takes place:

“I’m the kind of Christian who only goes to church on Christmas and Easter, and spends the other 363 days at the mosque.” “… I don’t think that’s a thing.” “Our rabbi swears it’s legit.”

Web Original

• Sanshinto or Tritheism in Tasakeru is based primarily on Shinto, but has elements from Greek, Roman, and Norse mythology. The species' differing beliefs draw from everywhere., even, according to the author, the Cthulhu Mythos
• The Chaos Timeline has the Indian Chandramoorthy develop his own religion, which combines elements from Hinduism, Islam, Catholicism and the classical Greco-Roman religion.
• Gamzee's religion in Homestuck seems to be based around fundamentalist and Rapturist Christianity, with a little Islam for flavour (he gets very upset about seeing video depictions of his Messiahs), and perhaps with a little Judaism (his ancestor was responsible for the persecution of the Troll Jesus), mixed up with stoner/hippie culture, and then all applied to Juggalo fandom. A parody, obviously. Word of God is that is was inspired by an Eldritch Abomination and his Manipulative Bastard Dragon, arguably making it a Religion of Evil.
• A Nuclear-Flu Doomsday (originally called 1963: Doomsday an fanon/fan-fic (within Alt-History wikia itself) by author himself before Admin reworked title as now) have very small minor of only non-Christian Amish community (prior switching their community's identity into Tribe as Tribe of Odin this year alone) in Maryland within Post-Nuclear and Outbreak world called themselves Thorists or Thorism that they worshipped Odin and Thor as only two main serious gods (put mistaken two as God and Jesus in appearance) while others deities are non-existant or impliying portayed them as mythical creatures along believing Norse mythology and continue most of there Anabaptist traditions/practices when originally founded religion in mid-80s during Mass "Neo-Norse Revolution" during the time.

Western Animation

• Futurama plays with a somewhat joke-y version of this trope in the First Amalgamated Church, headed by Father Changstein El-Gamal. Supposedly created from the merging of major 20th Century religions — Christianity, Judaism, Islam, Hinduism and Buddhism as well as agnosticism, and the logo shows it. Differs from more serious examples in that part of the joke appears to be that the Church doesn't have even a semi-coherent belief system and mostly just tries to be as generically 'spiritual-ish' as possible.

Father Changstein El-Gamal: Dearly liked, we stand here before one or more gods, or fewer; to join this couple in pretty good matrimony. If anyone objects to this union, may they speak now, or forever hold their peace; or do something else.

• The only thing you can definitively say about Reverend Lovejoy's church in The Simpsons is that it's some variety of Protestantism. In an episode where Bart and Homer convert to Catholicism, the Rev describes the One True Faith as being "the Western Branch of the Reformed Church of American Presbo-Lutheranism".

Real Life

• Certain Unitarian Universalist congregations can end up like this. Since UUism rejects the idea of central dogma in favour of emphasising the value of spiritual community, nothing stops any individual from being a Christian, Jew, Muslim, Buddhist, Hindu or even atheist/agnostic and still a practising UU. It's not too far from the truth to joke that that UUs begin their prayers with "To whom it may concern..."
• The proper term for this trope is Syncretism. As you can see, there are enough examples of it in Real Life.
  • In the 19th century, it was very common among scholars of world religions to gain a complete understanding of God by bringing the knowledge of all religions together to create a unified whole. While certainly admirable, religious authorities of all relgions where mostly unimpressed and didn't share the belief that other religions had anything to contribute to "their" already perfect models.
• This (text: "Basics of religious cultures and secular ethics") was a reaction on the introduction of this experimental "obligatory facultative" school course — which, obviously, managed to unite everyone, if only in condemnation of this offense.
• Messianic Judaism, which combines the main tenets of Judaism with a belief in Yeshua, or Jesus as Messiah. Most Jews consider messianics to be simply Christians by another name, or at worst, disguised proselytizers.
• Some Anglicans (Church of England) embraced Catholic spirituality and outward elements (i.e. Mass, the rosary, vestments) while still remaining with the Church of England. They're called Anglo-Catholics.
  • In the 19th century, it was very common among scholars of world religions to seek a complete understanding of God by bringing the knowledge of all religions together to create a unified whole. While certainly admirable, religious authorities of all religions were mostly unimpressed and didn't share the belief that other religions had anything to contribute to "their" already perfect models.
• The Eastern Protestant 'denominations' are this result, due of the (post-)imperial colonial nations in the 19th century and onwards, like the United Kingdom or Netherlands has to bring their Protestant missionaries into a Eastern Christian minority/majority geographical areas like in Eastern Europe, Africa, and India, of formerly break up (and usually unrecognized) Eastern Christian churches, who spite retaining their culturally Eastern Christian identity and occasionally liturgies or sacred rites, has been adopting a varities of Protestant theology and practices. With a small inversion, where the lesser known Western Protestant churches, has adopting the cultural Eastern Christian identity (as well even practices and liturgical rites too) instead, like the Believers Eastern Church of India and the Evangelical Orthodox Church of North America, Africa, and Sweden.
• Very common in East Asian cultures. While Judaism, Islam, and several modern denominations of Christianity forbid syncretism, major East Asian religions like Shintoism, Buddhism, and Taoism have no such restrictions.
  • Similarly, during the Middle Ages and even into the early 20th century, a form of Christian syncretism was common enough among the educated classes. Greek and Norse and Celtic and other ancient European pagan gods were often reinterpreted as Christian angels who had been mistakenly worshipped (whereas the gods of other parts of the world were often assumed to be demons who had been mistakenly worshipped) or reinterpreted as Christian saints who had been deified against their will.
  • The Mune Shinri, a web-based religion is a syncretic blend of Taoism, Shintoism, and Christianity. If Christianity forbids syncretism, and Taoism allows it, does that make it right or wrong?
• The Baha'i faith is arguably an example of this. It basically recognizes the prophets of a wide range of other religions (including Moses, Buddha, Jesus, Muhammad, and others) and claims that they all founded "the religion that was necessary (and possible) at the time", in a scheme for humanity's collective evolution, whereas Baha'i is (obviously) the appropriate religion for our own time. The actual belief system seems to be a syncretic mish-mash of (primarily) the monotheistic religions, with all the nasty bits taken out and a pinch of rationality and egalitarianism thrown in.
• This concept actually played quite an important role in initially winning over the Turkic and Mongol tribes to Islam, as the belief in Tengri was close enough to an Abrahamic monotheism that Turkic tribes such as the Volga Bulgars were able to look upon Islam and see a basically more refined version of their traditional religion.
  • The Mongol ruler Ghazan of the Ilkhanate also converted to Islam and argued that his ancestors' veneration of Tengri was actually a form of Proto-Islamic religion.
  • Also employed in the Dastans of Dada Korkut, a collection of sagas regarding Oghuz Hakaan, the mythical father of the Turkic peoples, where it is said that Dada Korkut (a figure similar to Merlin, or Odin) is said to have journeyed to Madinah where he spoke with Muhammad (PBUH) and accepted Islam, carrying that religion back to his people in the steppes. Over time, that belief in Islam was misinterpreted as the worship of the sky god Tengri. It's quite clear that this was added by Turkic chroniclers some time after their conversion to Islam in order to mitigate their pagan past.
  • This trope is probably also why Turkic-speaking Muslims tend to use the word "Tengri" (which is really just a generic term for god, like the Greek Theos, the Latin Deus or the Nordic tyr) along with the preferred Arabic "Allah" to refer to God.
• The conversions of many formerly pagan areas to Christianity resulted in a lot of this.
  • Mexico's Día de Muertos aka Dead of the Deadcombines the Catholic All Saint's Day with an Aztec festival.
  • South American Catholics often practice what were originally Inca religious festivals. For example, the parades with the statues of the Holy Family and major saints were originally done with the mummies of Inca kings.
  • What little we know of Slavic pagan beliefs comes mostly from extrapolation backwards from records of Slavic/Christian syncretism. The Slavs seem to have initially taken Christianity as simply an afterlife, while still paying obeisance to pagan spirits in day-to-day life.
  • Several Afro-Caribbean faiths such as Santeria mix Catholicism with the native religions of imported African slaves (Yoruba in the case of Santeria).
• Chapels in public facilities such as hospitals or airports have to accommodate anyone who wants to visit and pray, regardless of their religion. So they can become like this simply out of necessity— if four patients' families are Muslim, Hindu, Catholic, and Protestant, it can make for a rather eclectic prayer service.
• Interfaith families often practice a mix of both parents' religions. A Jewish/Christian family, Hellenist (Hellenic Neopagan)/Orthodox family or etc..., for clear example, might celebrate both Christmas and Hanukkah
• Historically, this was the case for most non-monotheistic religions. An ancient German could adapt very well to Celtic, Tengri, Greek, or any other gods you could name. Exactly what the relationship between the various pantheons was depended on the priests, but most laity simply accepted that All Myths Are True until their local priest told them otherwise.
  • It helps that polytheistic pantheons often included the same basic archetypes (Love Goddess, War God, patriarch deity in the sky etc.) and thus could easily be mashed together by explaining the foreign gods as alternate names for your own pantheon, as the Romans were particularly fond of doing, especially with their War God Mars, whom they believed themselves to be descended from.
    • According to historians the Roman, Greek, and other nearby faiths really are different branches of an earlier Proto-Indo-European religionsas they had developed after the conquerors merged with local peoples and developed in isolation over centuries. Calling them alternative names for the same god is, more or less, true.