After WWIII, the PRC along with the other defeated powers of the Comintern relocated to Mars, taking swathes of refugees with them. Many however were left behind and the victorious United States granted control of what was left of the mainland to it’s ally on Taiwan. Dome Cities like those on Venus sprouted up, designed to fend off not searing heat and acid rain but radioactive ash. The survivors were corralled into the cities, partly for their own good and partly to keep an eye on them. There was a deep paranoia of a resurgent Communist insurgency. This persisted in the regions which bordered the former USSR, and were essentially left to their own devices by a Nationalist government which wanted to hold onto what it could and not waste energy fighting for scraps of toxic heath.
Twelve years later, humanity went to war once again. The Mayans had predicted the world would come to an end in 2012 and they were proved right as the Axis and the Americans went to war. The war was total and all-consuming. The North Hemisphere was devastated, and the Southern Hemisphere was scarred. The lowlands slowly drowned in fallout, and every year the world grows colder, dryer and more poisonous. Life in the Northern Hemisphere persists in the mountains under very specific circumstances.
For the states of Southeast Asia, they threw their contingency plans in with their respective bloc, either helping to fund the Venusian Dome Cities, the Non-Aligned League’s space habitats or the Comintern’s irrigation of Mars. What remnants that have been left behind live a desperate existence essentially reverted to the medieval era. In Central Asia, the larger territories of the mountains encourage a nomadic existence, and it is a little easier for them to organise at something more complex than a village. But in former China, things are more complex.
Shielded by their relative isolation and their lofty location, Tibet has emerged as a great power. A new Dalai Lama has arisen to rule a new Tibetan Empire, but as the Empire presses against other survivor states at it’s boundaries, they increasingly look to claim the Mandate of Heaven and establish a new Chinese Empire, predicated on a radical, apocalyptic strain of Buddhism. Their main rival are the denizens of the Domes and mountains of Southern China, which since WWIV has reorganised as a technocratic, utilitarian state. The Municipal Governors, estranged from Taiwan since their appointment have established a feudal empire enforced by their control of life-saving technology. The ROC persists on Taiwan, still claiming the mainland plaintively. Scatters amongst the mountains and high ground of the rest of China, Neo-Maoists have taken control of the survivor communities. They maintain organisation via radio, but are essentially independent from one another and live little differently from the mountain tribes of Southeast Asia. Neo-Maoism is a religious tinge to it, venerating the Eternal Chairman. Warriors in power armour traverse the toxic wilderness, bringing goods from the Inner Mongolia heartland to maintain a slightly more civilised existence at roughly 19th Century levels.