[PTTG]

A series of Babylon worlds, where various nuclear wars brought about hellish conditions. (Although there may be annother term somewhere...) Except for extremely recent ones, many of them are safe to wander unprotected.

1983 -- Soviet false positive caused an errant first strike. Stanislav Petrov was not present. Present date 1999, the southern hemisphere is overrun with refugees, while warlordism rules the global north.

1983 -- Soviet inteligence failure caused a first strike in response to the "Able Archer" wargame. Western powers weather initial strike fairly well, due to fortuitous wargame prep. USSR command and control shattered. Nuclear terrorism with soviet broken arrows proves more devastating. By 2006, remaining global powers are paranoid police states, or else failed states.

1962 -- US opens with "limited" first strike on forces in Cuba after negotiations fail and the blockade is broken. Mixed conventional and nuclear war follow, particularly in Europe. Both sides finally escalate more than nine months later. The lengthy lead-up caused widespread bomb preparation, but also more arms build-up. Only bunkers remain in northern hemisphere less than three years later, and the radiation levels mean many groups remain in stasis.

1979 -- US false positive caused an errant first strike. Europe, horrified by the display of aggression, frantically declares neutrality and pledges aid to USSR. The divergence may have come earlier than the war itself. US almost obliterated entirely, and Europe-USSR coalition is struggling with the knock-on effects of the bombardment. 1995.

2011 -- Diverged in the 70s with high computerization of USSR, part of a series of changes allowing the nation to persist. Both sides extend influence into southern hemisphere. USSR uses ICBMs against internal threats on border with China; global war boils over from there. By 2018, the world was just starting to rebuild, and warlords and legitimate authorities are hard to distinguish.

2004 -- Diverged in 1938 with different NAZI leadership. Nazi Germany achieves a peace treaty after subjugating Europe. Decades later, a four-party global war eventually turns to nuclear bombing. Most nuclear contamination was actually released during the manufacturing of the nukes.

1772 -- Diverged in 200s, possibly 300s, with economic changes in Roman empire. An industrial revolution took hold in 1100 AD and in 1772 a diplomatic incident sees nuclear war between Uyrop and Bharata. The Americas suffer economic more than literal fallout.