Because there is not much in terms of the lore , we will need to think up some. Here are my efforts.
Lore:
Geopolitical situation
The geopolitical situation that led to the outbreak of the long-feared global nuclear war was prompted primarily by the onset of Germany placing long range strategic missiles along the coasts of Northern Sea and Artic allowing them to nuke England and USA West Coast, tensions also rose when Ireland allowed to place German short range nukes in their territory thus officially joining Axis.
The result of this crisis was an increasing build up and mobilization of long range nuclear air-force by all of the nuclear capable nations. Ultimately, a series of military conflicts in minor countries driven by World powers placed everyone on high alert in the year of 1987.
World War 3
It is not known who launched the first nuclear weapon that started the conflict but when first nukes left the ground it didn’t matter. The nuclear exchange that characterized the Great War lasted for only a brief six hours, but was unbelievably destructive and reshaped the climate of the world even as it caused the fall of most of human civilization everywhere across the globe. More energy was released in the first moments of the Great War than all of the previous human conflicts in the history of the world combined. Entire mountain ranges were created as the ground buckled and moved under the strain of the cataclysmic pressure produced by numerous, concentrated atomic explosions. Rivers and oceans around the world were contaminated with the resulting radioactive fallout released by the relatively low-yield nuclear weapons used by all sides, and the climate changed horrifically. All the regions of Earth suffered from a single, permanent season once the initial dust blasted into the atmosphere by the nuclear explosions had settled – a scorching, radioactive desert summer.
Aftermath
Despite the global destruction caused by the war, many areas remained habitable, with low and tolerable levels of radioactive fallout. The surviving humans were in some parts of Earth able to continue living in the ruins of the pre-War civilization, establishing new communities and even small cities.
Around a week after the initial nuclear explosions, rain started to fall; however, none of it was drinkable. The rain was black; tainted with soot, ash, radioactive elements produced by the nuclear explosions, and various other contaminants produced by nuclear weapons. This rain marked the start of the terrible fallout that marked the true, permanent destruction caused by the Great War. The rain lasted four long days, killing thousands of species that had survived the initial destruction of the bombs, be they animals, plants, or microorganisms. Those few living things – human, animal, or plant – that survived after the rain ended were left to live in the now-barren wasteland that had spread across Earth, where nearly all pre-War plant life had died either in the initial explosions or from the intense radiation produced by the fallout.
The Plague that followed
Most of those who died in the aftermath were burned to ash by remaining government forces so for the first few weeks disease was not a problem. After about a fortnight though this changed, many people with blast and burn wounds began to die and others fell sick with radiation poisoning. In Britain this was bad but a local problem. Martial law was in force and massive medical resources were directed to Manchester along with returning troops, there was little they could really do but they did at least see the bodies were buried avoiding an epidemic. As yet no one knew what the blasts were but one thing was obvious a lot of poison was in the air. Prime Minister ordered an evacuation of the area around the city, it didn’t help those already affected but it did stop things getting worse. Reich government in France followed a similar pattern at first but war damage combined with Radiation blowing in from Germany meant the problem was much worse. Cholera spread in many areas but for the most part things just about held together. Then the plague began.
It began in the destroyed cities of Germany during mid-July, the victims began to develop horrible blisters all over their bodies which burst and oozed infectious puss. The pain was enough to drive people mad and death was slow as blood oozed from the body in a long lingering death. Within a week it was in the water, by August it was everywhere in Germany. The disease was named “The blistering fever” but soon became known as “The living Death”. It infected about 70% of any population and of those 80% everybody died. Certainly no one was ever found who recovered from it. The horror of the disease was such that the victims were shot on sight but it was too late. The virus got across the border into France and still occupied Eastern Europe; from there it spread to the Ukraine and the Middle East. France passed it to England and though heroic efforts kept it from spreading into the water it still hit London or what was left of it. In following months half a million British people died. By early September it was all over the world. Millions died every day, until finally the onset of the worst winter in two centuries froze the disease to death. In two months “The living Death” killed almost a billion people adding up to the death toll that was lost when the bombs fell.
German Pre-War Norway and todays Mutants
Background
In the years immediately preceding the Great War of 1987 between powers of Axis and the Allies, both sides were scrambling to research a new weapon that would give them an edge in the coming conflict. German government-funded programs like SS Spezielle Projekte Abteilung (SS Special Projects Division) that began to develop secret biological weapons that could defeat the Allies. Most important their research was into immunity-boosting drugs designed to combat biological weapons agents that were developed by USA government.
One fear amongst the German military of this period was that the Americans would deploy biological weapons against German troops; these would be powerful, genetically engineered super-viruses that would decimate other armies and civilian populations without a single shot being fired. Thus, Germany had initiated the Ubermenschlich Evolution Project (UEP) to develop a way to stimulate the human immune system in such a way that it could naturally counteract any American biological agents. It was determined that altering the subject's DNA in such a way that its dual helical structure transformed into a quadruple helical structure would render the recipient immune to almost any known or engineered pathogen.
During SS Spezielle Projekte Abteilung testing phase of the Ubermenschlich Evolution Project in 1985, abnormal side effects were observed developing in the test subjects. The test animals began to grow dramatically larger in size and muscular structure, and their brain activity increased. Seeing the potential military applications of these unexpected results, the German Army sent its own military scientists into the facility to secure the project and renamed the UEP project as the Ubersoldaten project. Not content with producing mere immunity to disease, the Army's researchers hoped that the project would turn its soldiers into abnormally strong and intelligent supermen capable of defeating many times their own number of American soldiers. When the testing on animals reached its logical conclusion, the German military moved the entire apparatus of Ubersoldaten research to the Bunker 17 a Military Base in Norway, where secret human testing on military prison inmates proceeded.
New Reich
When the bombs fell, most of the generals and politicians of the Third Reich were caught in fiery flames of nuclear apocalypse, but some retrieved to secret bunkers that were built in occupied Norway where they remained and watched how their Fatherland burned. They were content that the National Socialism will live on in a New Reich. The New Reich is comprised of descendants of top-tier officials of the Third Reich government, elite members of various branches of the Wehrmachts military, as well as a few others. The New Reich takes pride in being the last known concentrated bastion of pure, unmutated humanity and being the most technologically advanced faction in the European wastelands. They are headed by one man, the Fuhrer, and obey his every command and are ready to reclaim Europe for the Aryan race.
The Children of Future
After bombs fell and world went into silence, many prominent researchers stopped their work in developing next superhuman but it all soon changed. They soon were contacted by newly established Nazi government in Norway and under their leadership resumed Ubermenschlich Evolution Project, now only trying to develop drugs that would give immunity to radioactivity. To do so many test subjects were brought in and the experiments were dealt on them. German scientists observed that the Ubersoldaten serum introduced to human bodies that were exposed to large amounts of Radiation created abnormal side-effects: test-subjects grew twice as big and strong. Soon in one experiment, test subject named ‘’Patiant 302’’ overpowered guards and set the rest of the test subjects free. With sparse resources New Reich government in Norway decided not to send the remaining military personnel and so Bunker 17 was lost to the test subjects.
It's 2137 now , and wanderers are reporting that strange creatures are stalking in Northern Norway and abducting people, nobody knows why.