The Unholy Reich:
I came up with this one months ago after a burst of inspiration brought on by insomnia. This is based on the ASB Nazis had secret projects researching weird science/dabbling in black magic along with other conspiracy theories and above all, crossover fanfiction that I could find and put together. The final catalyst for this was Quantumbranching/B.Munro's 'Thor meets Captain America' map (which credit goes toward along with the design for the Reich).
In 1944 as the tide of the war turns further a fanatical (and likely insane) SS officer finds a strange book in an attic from a house in an occupied town. Several months after reading the book he suffers a vision showing the destruction of the Reich and the future of Germany should they lose the war. Spurred on by this he eventually enacts rituals from the book and sacrifices his soul to unleash one of the Elder Ones within. Hlim'oarl the Angel of Death is summoned and the invading Soviet armies are obliterated by his fiery sword and body of 'divine light'. Meanwhile in secret hangers and bases across the Reich with the extra time bought certain Nazi projects bear fruit. Soon Nazi armies armed with laser weaponry, flying saucers and tank-like humongous mecha march under the protection of the Elder Ones.
In 1947 with victory assured in Europe a new cult dedicated to the Elder Ones overthrows the now insane and debilitated Fuhrer and takes his place with the support of an SS now dedicated to the creatures that gave them victory (Nazi mysticism along with fear of the abominations helped). The Third Reich is an enormous bloated entity stretching across Eurasia and much of Africa. The cities of the Reich are massive neo-Gothic hive constructs with entire districts dedicated to massive temple complexes where sacrifices are given to the Elder Ones to ensure their favour. Sacrifice is now the only form of execution as well as being a possible public service for any wanted volunteers. The state tries to confine it to only the undesirables and prefers to keep their Germanic and Aryan citizens away from the altars unless they insist on it.
Whilst a theocracy the Third Reich does also endorse the sciences. Nazi science often has a engineer's approach to it with discoveries often being around necessities and should a solution to a problem already exist then a new solution need not be researched. The Reich does still have a history of strange new discoveries as well as further development on their weird weapons. Anti-gravity engines have made flying cars and ships a reality and the Reich's cities buzz with swarms of beetle-like flying cars that flit between the massive black crystalline monoliths of the inner cities. Reich architecture is a strange combination of Gothic style combined with the impossible geometrics of the Elder Ones. Magitek is also a reality and the Reich has happily capitalised on it. Whilst effective AI is still a distant prospect it is possible to animate a mechanical golem with someone’s soul and bind it to a pre-programmed set of commands which is just as good.
Vampires are a somewhat common sight across the Reich. The result of the only successful attempt to create super-soldiers to support the SS, the vampires have now moved on to become the elite of the SS and the Gestapo. Several high ranking members of the Cult, Party and military have been volunteered to undergo vampirism and thus retain their ideological purity to ensure that the Reich truly does last a thousand years. What are less common are the sorcerers and necromancers that monitor the minds and souls of the citizenry in order to keep order. Alongside them is an enormous state security network consisting of both science and sorcery that monitors everyone in every way imaginable. Should dissidence and non-compliance exist in a citizens mind, that defies accepted levels (as decided by the government) then they are 'vanished' by the Gestapo and soon end up on a sacrificial altar or a laboratory table.
The leaders of the Third Reich are now all members of the Cult of the Elder Ones with leaders dedicated to different deities and departments of the Reich. The leaders are all certifiably insane to some degree and many members have been 'blessed' by the Elder Ones. Others have been augmented by science, sorcery or vampirism to increase their effectiveness in government. Most other Nazi officials and high-ranking members of society are affiliated with the Cult to some degree and anyone who wants to progress in society has to make some donation to the Cult in some way (assuming you can pass the racial and ideological tests).
The United Kingdom soon found itself truly alone against a Europe dominated by an insane Third Reich as the Nazis finished mopping up the last of the Europeans. The UK experienced another attempted Sealion but by this time had deployed a few trump cards of their own. The previously secret agencies sponsored by the Crown deployed their arsenals and soon RAF planes augmented by alien technologies and UK special operatives endowed with supernatural magic and abilities obliterated the Nazi flying saucers and warships. However with the arrival of the Elder Ones and Elder-spawn the UK began to look to more desperate solutions. It was then that the the UK's salvation (in a relative sense) appeared. Beings offering safety from the Elder Ones contacted the UK. They spoke through the minds of the entire nation at once. As the Nazis rampaged across the South Coast and headed towards London with all their horrors the UK accepted the terms of the contract presented and offered their belief and faith in the beings that revealed themselves as Witches. As the Nazis approached London an army of theatrically dressed beings appeared in the air above the army. In a matter of seconds the Witches unleashed a horde of spirits and familiars along with flurries of spells that devastated the SS forces and forced the Elder Ones back across the Channel but no further.
The UK is now a strange nation. The entirety of the nation is specifically designed to certain patterns set down by the witches and the country is now dotted by way-stones and protective circles and wards that keep the Elder Ones at bay. The rest of the nation looks like a demented version of Wonderland with nonsensical and thematic architecture alongside random tracts of uncontrolled wilderness. Architecture not directly linked to the Witches designs often have a neo-Classical and Victorian aesthetic. Most cities in the UK are macabrely decorative similar to a disturbing fairy tale city. The UK is filled with special angelic statues that support the UK governments surveillance. Visitors to the UK will often find that several of these angelic statues will often switch places and positions when you’re not looking. The UK government is aristocratic per the Witches demands and are most likely insane in some way as well. Government policy is often decided through certain rituals to decide policy with the proceedings often watched by a Witch as an associate of their Senate. The UK Prime Minister is also a contractual associate with the Witches and contacted by them through a disturbing portrait found in their office in 10 Downing Street. The UK is by necessity a militarised one and has often be criticised by the USA for their belligerence (among other things of course).
The Commonwealth has shrunk since the beginning of the Second World War (still technically ongoing). The White Dominions are now just as powerful as the UK itself and are now just as closely associated with the Witches. The remaining colonies however are areas where the Witches cannot directly intervene due to a lack of belief from the natives who have not accepted the power of the Witches. Order is retained through conventional forces that are reinforced by reverse engineered alien technology and genetically and magically engineered creatures and soldiers. India is the most controversial region of the Alliance. Whilst still a Commonwealth Realm and owning its own magical aristocracy it is very different from the UK. It still suffers from religious terrorism due to the presence of the Witches and is very culturally diverse as the local culture picks up elements from their colonists and then hybridises it.
Judging by the readiness by which the Nazis took to invading and absorbing Italy after they objected to the Reich's 'Deal with the Devil' it was quite obvious to the Japanese that the Germans were not going to accept their impure existence in a Nazi dominated world. To this end they worked hard to find a means of defending themselves whilst the SS ground their way through Siberia and China. The Japanese did not have any alien technology to use and though an alien was eventually uncovered she (it looked female anyway) simply joined up with several others, abducted the family that had found her and fled for deep space. Salvation came for the Empire as the first Luftwaffe anti-gravity ships and flying saucers appeared. As they approached a massive bank of fog grew around the entire island shrouding the invaders. An enormous silhouette appeared on the fog that surrounded the Home Islands that day and with a single gesture the entire Nazi invasion force was struck down with debilitating madness. The SS personnel all clawed at their bodies until they bled to death or turned their weapons upon themselves and the invasion collapsed. The Cult attempted to call upon the Elder Ones but found Japan beyond their direct influence much like Great Britain was. Japan survived.
The Empire of the Rising Sun is now confined to the Home Islands, Taiwan and some of the Pacific Islands they picked up. They have reconciled with the USA and UK and are now a key member in the Alliance. Japanese society is militarised as well and keeps Japanese traditions. Society is also geared towards belief in order to support the deity that protects them from the Elder Ones. However there is a sinister side to this agreement. The Japanese deity does require sacrifice to sustain itself. Every year at a certain date every community in Japan loses two people to feed the deity. The body of one can be found far away but the other disappears never to be found. One necessity has been the implementation of measures to keep the birth rate up to compensate for both the sacrifices and the losses in the on-going conflicts in the Sea of Japan and abroad. New technology from the UK and USA has allowed the Home Islands to accommodate and feed a massive population but it is still a struggle. The Japanese people are often seen in some state of fear or paranoia, as a part of the worship of their God requires fear for her powers to work*. Japanese culture is still very traditional and has managed to avoid the Westernisation of OTL but is still the lead in the market of cultural exports (just after the UK and their weird culture).
Through the efforts of the whole Alliance, South East Asia was preserved from the Reich's invasion. Due to the lack of faith on the part of the locals neither side was able to use the power of their supernatural benefactors to preform pre-emptive attacks. The entities were still effective in the proximity of their respective armies however and so were deployed alongside their other weapons. The battles fought in Eastern China were especially brutal and eventually a status-quo was established with a 'No Man's Land' stretching for miles just North of the River Yangtze. Free China is a brutally oppressive military dictatorship that has used technology developed in or donated from other Alliance members to modernise and fortify their nation. China is becoming the factory floor of the Alliance with massive industrial complexes churning out weapons ammunition and certain reproducible arcane artefacts. China is more traditional than OTL having never undergone the destructive Cultural Revolution but they have imported certain traits from the rest of the Alliance that came along with the mystical protection provided to them in order to keep out the Elder ones. China is still under the rule of Mao Se Tung who despite his age (which should have killed him long ago, the US suspects foul play on his part) is still giving the orders in government. He is backed up by an incredibly authoritarian police state that guards the minds and souls of the people from the Reich.
North of China is the enormous line of territory that is kept in a state of perpetual armament/combat in order to keep the encroaching German forces out. There is no official boundary which is what lead to this state of affairs but it does provide the unofficial border between the Reich and China.
The United States of America is the odd one out in this world as they have not turned to Eldritch Abominations or similar beings in order to survive. When the situation became painfully obvious to the USA there was a reactionary panic. The US government refused to resort to making a 'Deal with the Devil' and to the present anyone who has seriously proposed doing so has been shouted down and often lynched. The US thankfully did have a secret hanger in Arizona filled to the brim with supernatural artefacts and alien technology that the government eventually made public and began to utilise and allow large-scale research be performed on them. Whilst possessing no entities to defend themselves from the Elder Ones directly they begrudgingly acknowledged that the existence of their allies protecting entities is keeping the Elder Ones away from them.
The United States is still a democracy and tries to be an example for the remaining nations of the Earth. They do understand that the situation of their British and Japanese allies justifies their bargaining and insanity but still find them unsettling especially after the influence of the Witches spread across the Atlantic to Canada. There is a subculture across the country that has reacted strangely to the awakening of the entities and there has been some immigration to Japan and the Commonwealth to witness the strange magic of the rest of the Alliance. On the other hand there is a very large group of Americans that reject associating with heathens that sold their souls to monsters and think America should have nothing to do with people they say are as bad as the Nazis. There was an unfortunate backlash from the American religious community after Jesus and All Saints failed to show up to rescue the righteous from the minions of Satan but that has finally quieted down and the terrorists have become rarer and rarer every year.
America is a land of scale where alien technology has allowed for the construction of enormous buildings, vehicles and road networks. The USA is still a capitalist society and certain companies that were leased alien technology have successfully reverse engineered most of the products and are still marketing the new innovation brought from them. The US also leads an alliance of nations across South America that was lashed together after the war with the Argentinian Reich and their hordes of ghouls, madmen and Elder-spawn. This union of the Americas lead by the USA, is a superpower in and of itself and is the lead member in the Grand Alliance.
Technology in this world is a varied mix. Anti-gravity tech has allowed for genuine airships to ply the skies and after new innovations even go underwater. New communication systems allow for thoughts to be transmitted though some truly embarrassing scandals have been caused by them. An internet equivalent exists but is heavily monitored for illegal magic based activity. Power is now mostly provided by quantum reactors that harness the power that is bled off from controlled tears in reality (however the connection between these reactors and the insanity and suicide that afflicts technicians has been noticed by many). Other sources are from new alien techniques that have made releasing further energy from the atom possible. Alien technology has made it possible to cure most contemporary diseases but new diseases, mutations and bioweapons keep pharmaceutical companies on their toes. Magic has also helped advance new forms of hybrid technology that whilst risky have provided solutions to many problems. Psychic abilities are another dangerous scientific field. Numerous psychics have been discovered but their powers vary and many can go insane if they are not ready for certain events. The direct presence of the Elder ones and other entities has boosted humanity's psychic power as a whole which may be the main reason why so many powerful psychics have emerged since then.
There has been a recent growing phenomenon across the world of unlicensed magicians. They are more often than not adolescent girls that work with far more unorthodox abilities than regular sorcerors. Government agents have noticed that the appearance of these 'magical girls' as they've been unofficially termed, is often proceeded by a strange white animal that phases in and out of detectable reality.
Military technology is by far the most developed. Tanks have now been completely replaced by more flexible and versatile mecha with the new sleek British designs replacing the older clunky American models. The Japanese have been dabbling in some truly disturbing technology that was uncovered during an expedition into Antarctica (the accounts of the expedition have yet to be made public) and produced some very disturbing giant mecha but have been forced to resort to child pilots due to some strange psychic resonance requirements. However they have become a necessity as some new Kaiju sized Elder-Spawn have begun to appear and are capable of penetrating the mystical defences around the Home Islands. Weather control devices manipulate the weather watering crops, or devastating enemies whilst strange devices manipulate space and time to teleport whole armoured divisions far behind enemy lines. The Reich utilises fleets of anti-grav ships and flying saucers that float above legions of cybernetically and magically augmented SS soldiers, vampiric warriors and divisions of mecha. Floating fortresses and eldritch sea monsters scour the oceans to intercept Alliance submersible warships and aircraft carriers.
Outer space has become the new ground for expansion and anti-gravity ships float above the atmosphere. With truly destructive MAD making Earth less of a viable target and battlefield, the world powers have begun to look to the stars as a source of resources or as a refuge from the monsters that have taken control of the Earth. Vacuum however means nothing to the Elder Ones, the Witches and the other entities and as humanity heads to the stars they bring their benefactors with them.
In this universe Faith is the psychic amplification of multi-dimensional entities. Demons, Witches and Gods often have difficulty manipulating reality to sustain themselves and use their abilities by themselves and so the psychic acceptance and belief in their physical manifestations is often necessary for them to emerge and act upon the physical plain. It also explains why entities often have trouble appearing in areas given over to the belief of other beings. Human sacrifice is another form that harnesses the psychic energy release that occurs from death especially the trauma of violent death (areas reporting sights of the strange white animal have seen sudden massive spikes in psychic energy that inexplicably disappears).
However as the influence of the entities reaches its zenith the world continues to change. In the Reich plans are drawn to solve the problems of the last remaining sub-human nations and their blasphemous sponsors. Against this the Allies continue to draw plans that if they cannot remove the Reich they can deny them outer space and use that as a refuge to flee the Earth. Meanwhile in a basement in New England an ancient and disturbing chimera-like statue in the back of the room has been exuding energy for decades now but the readings have begun to fluctuate chaotically and a sinister presence has begun to manifest itself in the room around the statue.
P.S-Most of the Elder Gods are my own creations. The rest of the material is from or was inspired by Iron Sky, Command & Conquer, Higurashi/Umineko No Naku Koro Ni, Code Geass, Evangelion, Hellsing, Captain America, Puella Magi Madoka Magica, Doctor Who/Torchwood, Franken Fran, Tenchi Muyo, Harry Potter, H.P.Lovecraft, My Little Pony Friendship is Magic, Godzilla and other similar works.
*The deity that protects the Japanese is not actually as bad as she is described but she has bosses to please as well and her own regulations, red tape and boxes to tick. However those who are able to appoint a meeting with her High Priestess and her ‘extended family’ can actually contact her. It is often a jarring experience.