Welcome to Kaiju Earth - A world of monsters

In the closing days of the Second World War, a matter of days after the "Trinity" nuclear bomb test in New Mexico, the first of the monsters appeared. It was thought that the detonation and the resultant release of radiation woke the beast from it's slumber, but many have come to believe the idea that humanity reaching the destructive power of nuclear arms spawned a kind of "Immune Response" from the Earth itself. Regardless of the cause of the monsters' arrival, the war, and the world, fell apart quickly once they appeared in numbers. The hardest hit places were Japan and Europe, as many monsters moved south from the Arctic Circle, destroying everything in their path; by the time resistance was organised, human civilisation was all but eradicated. 

Humanity itself, however, survived. Some went underground, some fled to the countryside and some even stayed where they were to take their chances, but life did indeed go on. After the initial surge, monster attacks against humans became less frequent, but clashes between the giant beasts would cause massive collateral damage, an occurrence that led to a focus on the rebuilding of military and development of new technologies. Whilst tanks and jets could rarely damage monsters significantly, on a good day traditional munitions could drive them away from civilians. In order to build these new forces, two new nations began to arise from the rubble of the past years. 

Due to it's sheer size, a reasonable amount of the governmental structure of Soviet Russia survived, though Stalin and his Politburo were long gone, what remained was able to restart agriculture and industry West of the Urals. Following on into the ruins of Europe where they were permitted (or often just not resisted), the Communists started communal farms and factories to restart society. Although no true central government arose, the communes began to cooperate to defend themselves and build new technologies. 

Far to the East, the Nation of Japan was rebuilding as well, though with a major advantage. Among the first monsters (or Kaiju in the native tongue) were several that hailed from alien worlds, attracted, it has been theorised by the presence of native Terran Kaiju. After these battles had ended, usually in the favour of the native Kaiju, the Japanese people took the technology in front of them and used it to lift themselves up. Whilst much of Europe struggled to recover the world they had lost in 1945, the Japanese soon found themselves in a futuristic new society. 

It was not only the Japanese that took advantage of alien technology falling from the skies, Doctor Douglas Birely, an outsider genius who had predicted both the Hollow Earth and Kaiju, saw the new world before him as an opportunity to get revenge on those who had laughed at him in the past. Seeing that the aliens had some way of controlling their own Kaiju, Birely sought this technology out, re-purposing it and declaring himself "Doctor Demonicus". Operating from his secret "Monster Island", Demonicus sends out mind-controlled Kaiju to do his foul bidding. 

The origin of the various alien invaders that the Kaiju have attracted remains much of a mystery, despite a tendency towards monologue and intensive picking-over of ruined technology. Some reports indicate within the Solar System, possibly Mars or Venus, but contradictory information speaks to their coming from much further away. Whilst the aliens first appeared in the wake of the initial Kaiju attacks, it is now thought that they were attracted to Earth by something that also appeared in the wake of the Kaiju; Energex Crystals. 

What is Energex? No one is yet quite sure, but what is known is that Energex is the richest source of power on the planet. Just a few grams of Energex can power a farm for months, or a battle-mech for seconds. When refined into cube form, the value of Energex is critical to every society and military on the globe, even the Kaiju themselves seem to need to consume Energex as part of their life-cycle. Just why this is and just what the connection between Kaiju and Energex could be, only time will tell...