[b][u]The Eternal Church[/u][/b]

An extremist, radical offshoot of a Christian church from the US Mid-west, the Eternal Church was founded by a fire-and-brimstone preacher and his family after they were found too radical for other churches and groups. 
They appeared during the 1990's and were of little note, other than numerous cautions and overnight stays in the local jail for disruptive and anti-social behaviour for some of their extremist protesting and demonstrations, especially at sensitive occasions. 
Their church managed to grow through appealing to the downtrodden, outspoken, and overlooked; offering them a place to be themselves, appealing to their nature and desire to belong, and giving a voice and attention to their views, and offering approval from on high for their radical thoughts and ideas. 

The Heavenfall was a - literal - godsend for them, as they claimed it was a holy act of retribution for all of societies' excesses, and punishment for the heathens, blasphemers, apostates and sinners. Their survival - being as how they were already partly an apocalyptic survival cult, and had squirrelled away supplies and shelter - and then their sharing of these supplies with their local community and providing a measure of disaster relief and preaching their survival and the impact itself as divine action, encouraged more to their side. 
Among these were several notable and high-profile converts, whom used their influence, following and wealth to further the message of the church, and it quickly took on a much larger, higher profile, message and scope. 

At the same time, the apocalyptic element of their preaching, along with the elitist aspects and selectivity became more and more involved. The group grew larger - almost improbably - and they clashed and butted heads with local authority more and more. Illegal weapons charges, refusal to allow access to law enforcement to their compounds and facilities, and even suspicion of coercion, abduction - especially of minors - and other major and minor charges were all levelled against the group over time, as well as numerous country of evading arrest, violation of parole, failure to show up for court, and violation of conditions of bail. 
There were also frequent accusations of threatening and destruction of property of other churches of religious organisations or groups, and especially against non-Christian denominations and faiths. 

Eventually, with so many charges levelled against them, the group - now calling themselves the Eternal Church - left the USA and moved to a compound in the ruined wastelands of what was Russia, hiring mercenaries and PMC forces to take control of the area, and carve out their own territory. 
Isolated and with no law but their own to follow, they made quick work of fortifying their position and establishing a functional, self-sufficient territory. 
Their beliefs and ideology grew more and more obscure and layered in shadowy ritual, twisting and obscuring the original words of the bible and judeo-christian beliefs into something outlandish, extremist and mired in layers of secrecy, interpretation and contradiction. The exact nature and word of these texts are unknown to outsiders, but the idea of eternal life through diligent and ceaseless service, faith, belief and sacrifice to crusade against the heathen belief and lifestyle of outsiders is the only way this is guaranteed. 
Recruitment into the church is selective, but targeted, and induction involves brain-washing techniques and forced separation from friends, family, and installing feelings of belonging, and of a new family. Leaving or doubting is framed as betrayal and is associated strongly and heavily with ideas of guilt and shame. 

The Eternal Church uses vicious tactics against those it and its' faith see as threats or the focus of its' hateful and isolationist preaching - liberal governments, alternative lifestyles or families, other religious groups, and virtually anything else they see fit at the time. Capture of resources and materials to expand their infrastructure, influence and power are also frequent targets, and have made the group a destabilising regional influence. 
Internationally, groups of 'missionaries' travel worldwide to 'preach' their faith, often in secrecy as the group are considered a terrorist organization by the N/UN and many other regional or international groups. 

Though they currently possess little in the way or military-grade vehicles or aircraft, this has been slowly changing as their influence expands and grows, and they are known to possess substantial ground combat forces and self-defence weapon systems.