Or Christianity in the interstellar age.

Though it still accounts for 500 million believers, Christianity has suffered in the Low Age and beyond, shattering in several successor faiths that spread alongside the weird paths weaved by humankind between the stars.

Catholicism has gone through a schism -- a centuries-old habit reminiscent of the Middle Ages, though in this case, the fracture is more geographical than theological, between Earthbound believers and xeno-churches. On humanity's home planet, the pope has been sitting on the golden throne of Saint Peter for more than three hundred years, to the point they do not even have a name anymore: they are just the Pope. Once, they were known as Thea, a small AI-adjacent program tasked with saving, compiling and analyzing more than two thousand years of theological scriptures. As time passed, Thea slowly grew within the Vatican, swallowing servers and buildings until it had become the nigh-entirety of the Holy See. The cardinals ended up electing Thea as the Pope, not without a strong debate revolving around the divine nature of AI, but at this point, they were little more than the system's janitors. In the present day, Thea has effectively devoured the entire Vatican, their mainframe visible from space as a vast golden growth outlining the borders of the ancient theocracy. Powered by a fusion reactor installed beneath Saint Peter's basilica, Thea has been mostly dormant for almost a century now, spending their time churning out theological advice on everything and anything, from the soul of aliens to the exact colour of archbishop garments. This hands-off approach has led to a general stagnation in the doctrine and hierarchy of Earthbound Catholicism, to the point, it would be strikingly recognizable for a 21st-century believer. Old, stuck with archaic traditions, Earthbound catholicism is a living fossil that only carries on through sheer inertia. 

On the other end of the schism lies the Cathedral Conclave based on the eponymous station, an offspring of Earthbound Catholicism that differentiated itself through the staunch refusal of Vatican rules and influence. The Conclave has an antipope, Joan III, as well as its own doctrine, which is a rather peculiar mix of catholic and protestant influences with a limited set of sacraments (only 4, compared to the official 7) and the possibility of ordaining female and non-binary persons as priests. Conclave churches are heavily inspired by mosques and Roman basilicas, and its clergy often wears dark colours, in stark contrast to the white, red and gold garments of Earthbound priests. The relationship between the Conclave and the Vatican is awful, with both popes having excommunicated each other -- an anathema that doesn't prevent the Conclave from being the face of catholicism in the stars. One of its notable sister-churches is the Ethiopian Catholic Church, that has ceased to follow the Vatican and instead opted to find a new life in the stars, under the Conclave's wing.

This two-way schism is further complicated by the existence of the Outer Church, a protestant, Marxist-evangelist church that directly comes from the Low Age. Having pioneered the second space age from the ruins of India and western Europe, the Outer Church refers to God as a woman, has only three sacraments (baptism, first orbit, first FTL translation) and enshrines major stars as saints. Though its Terran holdings have been swallowed by the USRE, the Outer Church still has a larger secular presence than the other catholic churches, its holy orders owning ships, space stations and even a few planetoids at the edges of human space. Entertaining very good relationships with the Omphal and the Starmoth Initiative, the Outer Church is a hybrid power that is on its way to being recognized as a qith in the Traverse. Neither the Vatican nor Cathedral Station have recognized the Outer Church, though the Popes have always refrained from excommunicating it -- probably because it would be entirely useless.

Aside from the Outer Church, Protestantism has been spending the last five centuries doing what it does best, being a sheer annoyance to the Vatican and fracturing in a thousand new movements. Protestant churches are too numerous to count, but they can be found almost anywhere, be they small religious communes with a few dozen members or vast space stations centred around spaceships turned into temples. The sheer diversity of protestant movements in human space is something to behold, and it can be argued that modern Protestantism is where true Christian theological innovation can be found.

The orthodox church has found itself a rather interesting niche as one of the main faiths within the Moon Communes, with its structure based around a communion of self-administered churches being very well adapted to communal polities. Having opened the ranks of its clergy to all genders under the influence of its lunar patrons, the orthodox church is extremely well-represented within space-bound communities, and especially shipbuilders -- orthodox priests can sometimes be seen blessing launchers, space drives or geometry engines in shipyards, which is always a sight to behold. 

The Omphal is the single most powerful religious organisation in human space and by all accounts a quasi-state in terms of power, capability and reach. This is not the first time in post-industrial history that religious societies have reached such a stage; among other examples, there is the notable precedent of the Outer Church, which pioneered early space flight in the Low Age. The Omphal, however, doesn't have a religion, or if it does it's in the loosest sense of the word.

The ideology of the Omphal is absolute inclusivism. In the eyes of the Omphal, there is no absolute religious truth. All religions and beliefs are correct, all at once, even in their contradictions. Divine revelation is a continuous and progressive process, with the teachings of every single religion in the world just being an aspect of this truth. Crucially, the Omphal also believes that divine truth is incomplete and as such, there is no way to determine which religion is more correct than others. This incompleteness is radical. It is radically impossible to access the divine truth. The only elements humans can deduce are the shattered aspects of unfathomable concepts which the various beliefs of humankind translate in their own way. The diversity of religion actually reinforces the understanding of this divine truth, as each of them casts a different light on it. Each religion has to be nurtured, understood and protected. In fact, even atheism is integrated in this ideology, as the undying faith in a world without the divine. Faith is the most fundamental aspect of human experience and the Omphal will protect and sublime it.

The Omphal was founded out of the ruins of the Outer Church and currently takes the shape of a religious cooperative not unlike the Marxist Outer Conclave but with radically different means and ends. The Omphal exists alongside human religions as an umbrella organisation that tasks itself with furthering the understanding, establishment and coherence of human faiths. The Omphal is always remarkably open about its goals and, probably inspired by the ultimate fate of the Outer Church at the hands of the USRE, always tries to work with or alongside planetary communes.

The Omphal itself is divided into orders, or Lodges, which are first and foremost styles. The organisation has a very peculiar relationship to rituals, symbols, chants and writings. Religion is illusion and the Omphal will never argue against this. It simply considers that, with the absence of absolute divine truth, this illusion is what constitutes the heart of religion. Omphal buildings are vast cathedral-like structures that display a staggering syncretism of almost every faith in human history, filled with incense, colourful symbols and golden jewels...or sometimes simple, austere chambers reminiscent of the simplicity of ancient cults. Members of the Omphal, when in service of the organisation, often refer to their Omphal persona using xe/xem pronouns, regardless of their usual pronouns.

Based on Cathedral Station and Mundis, the Omphal currently has five main orders.

• Order of the Moon: a surviving order from the Outer Church which acts as the Omphal's diplomatic and cooperative branch. Its members wear simple black and white apparel and often use feminine pronouns regardless of their gender. The order of the Moon entertains its own sub-religion dedicated to its mythical founder, Saint Jyothi. Many of its members are former or active Solar Envoys.
  
• Order of the Path: this order wears red and white/gold. It is often considered as the most flamboyant order, maintaining a small fleet of ships that take design clues from Hindu temples and gothic cathedrals alike. Behind their cowls and veils, the members of the Path are skilled spacers and navigators, offering their services to pilgrims and priestesses alike.
  
• Order of the Pillar: wearing simple white tunics, the members of the Pillar are engineers, architects and land planners who are dedicated to cataloguing, maintaining and in some cases building places of worship, regardless of religion or belief. The Pillar is mostly active on Earth due to the sheer density of historical buildings on the planet.
  
• Order of the Lodge: the Lodge is an order of librarians, theologists and historians that keep and maintain records of the complex history of human religions with the end goal of creating a universal encyclopedia of spirituality, a massive undertaking which they refer to as their "paper cathedral". The members of the Lodge are almost as flamboyant as the followers of the Path, adorned in gold and white, followed by the scent of incense and the sight of candles floating in zero-g.
  
• Order of the Shattered Star: members of the Shattered Star never show their faces, hidden behind veils, ritual masks and shifting q-augs. They are the most secretive Omphal order, invested in the strange art of xenotheology, the study and occasional worship of non-human deities. In public, they wear long black robes covered in silver ornaments. During digs and expeditions, they like to use voidsuits equipped with biomechanical tendrils, anti-radiation robes, additional artificial eyes and drones shaped like human skulls. It is uncertain if the Shattered Star is putting an act for unknowable alien deities or if its members genuinely enjoy their well-defined aesthetic. 

"We have never ceased to believe."

Religion in the interstellar age is a vast and complex topic that requires to consider the matter of religion during the Low Age.

In the post-industrial context of the Low Age, religious or para-religious orders played a very important role in conserving knowledge and cultural achievements from times past, though this does not mean the Low Age was necessarily more religious than the industrial age. In fact, many of the religious or spiritual orders born in the Low Age evolved into powerful communes and cooperatives which slowly lost their religious nature to turn into more secular organisations. The best example of this phenomenon is the various Muslim and Christian orders that coalesced into the Moon Communes. Aside from this prevalence of religious orders, the Low Age saw sweeping changes in the worldwide religious landscape, both through the evolution of historical religions and the creations of new ones, often forged in the intellectual renaissance of the solarpunk movement. Most of these changes have carried over to the interstellar era, where spirituality plays an important role, especially in isolated settlements that try to develop their own identity.

Yoruba Syncretism is the only major modern religion that was truly born in the Low Age, albeit it predated it (and most monotheist religions) by several thousand years. Though it originated in the homeland of the Yoruba people in Nigeria, this Polytheist-Animist religion also birthed numerous lineages in the Caribbean and Latin America during the pre-industrial and industrial era. Intense syncretism with various African traditions, Islam and Christianity during the Low Age gave birth to what is commonly described as Yoruba Syncretism -- a complex, multipolar religion with a multitude of Orishas, or deities, and a supreme God that is sometimes merged with Allah or the Christian God. As Nigeria and Kenya became superpowers during the late Low Age, Yoruba Syncretism became the face of the Africa-led "second space age" and thus spread to many extrasolar worlds, becoming one of the largest human religions. In present day, 650 million people follow Yoruba syncretism. The African city of Ile-Ife and the African Space Elevator are the main sacred Yoruba sites. 

Christianity is still present under various shapes, albeit it remains mostly confined to the Earth, with the planet acting as a religious beacon, especially for Catholics. The various schisms of Christianity, by far the most chaotic modern religion, are described in greater detail here. The Outer Church is often lumped under Christianity due to its Marxist-evangelist origin in the Low Age. However, whether or not a religion that describes God as a woman, celebrates the stars as saints and FTL translations as sacraments has anything to do with Christianity anymore is an exercise best left to theologians. Christianity is what Christians want it to be, and while it is mostly established outside of the Earth, the Outer Church remains a fascinating example of how the FTL era shaped the old religions. In total, a little more than 600 million people identify as Christians, mostly on Earth in the Socialist Republics of Europe and Latin America.

Islam was significantly reshaped by the Low Age. Though the Sunni/Shia divide is still alive and well, the real line of fracture within Islam is now between Terran, or Traditional Islam, and Interstellar Islam. Though Interstellar Islam shares a very similar theology, it has a completely different reading of FTL travel. Traditional Islam sees the geometry drive as a tool. Interstellar Islam sees it as an instrument of Allah, a paracausal device intended to reveal the beauty of creation. Interstellar Islam mosques will often have a geometry drive in their mirhab, and its imams generally double as pilots or navigators. While both Muslim movements go on pilgrimage to Mecca, Interstellar Islam allows its followers to replace the Hajj by a pilgrimage to Darb ut-Tabānah Station. There are 900 million Muslims in human space, making Islam one of the driving cultural and religious forces of present-day humankind.

Hinduism is often considered as the de facto religion of the USRE due to its Indian origins, albeit Islam could readily dispute that claim. Modern Hinduism didn't significantly change during the Low Age, save for the loss of several holy sites due to climate change and their replacement by new ones. Its sister variant, often called Eloran Hinduism due to its birthplace on the solarpunk world, is very similar on a surface level. Yet, Eloran Hinduism is better understood as a form of polytheist syncretism, where Hindu deities coexist alongside Shinto and animist influences, and where Saraswati is considered as the main deity -- which is reflected in the fact that the Saraswati Arcology, towering at 5,000 metres above the Eloran sea, is the holiest site of extrasolar Hinduism. Both Hindu currents total more than a billion followers, making Hinduism the most prominent human religion.

Buddhism remains relatively confined to the Earth, albeit many Buddhist enclaves can be found in extrasolar space. As a religion, it went through the Low Age remarkably unchanged, albeit its expansion to outer space led to a flourish of new aesthetics, where historical Buddhist temples are the exception rather than the rule. In total, Buddhism claims 400 million followers across human space. Aside from its historical sacred sites, modern Buddhism also considers the South Asian Space Elevator as a pilgrimage site, taking the elevation of the soul to the letter.

Animism is probably the most "artificial" category in religious census, as it covers not a single one but a myriad of religions revived by the Low Age, from the various currents of African animism to modern ancestor worship as practised in the Irenian Enclaves for instance. 400 million sophonts self-identify as animists, among which a surprising number of artificial intelligences. Animism also covers spacer shamanism and the various "star cults."

About 200 million sophonts identify as religious, but without belonging to one of the major religions; the main minor organized religions in human space would be Judaism, Sikhism modern Neo-Paganism and the Yazidi faith.