A timeline taken from the main rulebook.
2049: In the South American Andes, a new species of slime mold is discovered. It is hoped that this mold can be used in a computer (see: The Crawling Garden)
2055: The completion of the Grand Unified Theory results in the first workable quantum computer. Performing millions of complex calculations per millisecond, humanity's technological progress seems hopeful.
2063: A theoretical physicist announces the 'Ego Dimension Theory', a radical conclusion to the multiverse problem. Denounced because it was so religiously centric, he is dismissed.
2065: The physicist that announced the EDT is murdered by an unknown group.
2076: Desertification, rising sea levels and air pollution gives rise to a new agency monitored by the UN. It researches ways to deal with the negative effects.
2088: The slime mold discovered in 2049 finally is integrated into the quantum computer. The computer is able to learn at an astounding rate. This prototype is constructed in various development labs around the world.
2091: Local weather manipulation is a success. Meteorologists conclude that weather will become predictable within the next decade or so.
2099: Nuclear power is now the leading source of energy, after oil wells have started to dry up nearly forty years back. Coastline facilities, however, are at risk of rising sea levels.
2100: The Middle Eastern Water Wars begin. As desalinization plants are monopolized by governments, a revolt begins due to the lack of water.
2101: The murderers of the EDT physicist are revealed to be a large European organization. They have been working with the stolen EDT and the Slime Mold Computer to create artificial consciousness, albeit unsuccessfully.
2103: The Water Wars intensify as weather machines become practical. Constant rain on Middle Eastern cities cause increased dryness in other areas.
2109: Southeast Asian countries have increased reports of people going missing. Of course, this is chalked up to organized crime, and is ultimately ignored. The Water Wars have spread to South America, and the deserts are beginning to overtake jungles. Suspecting that neighboring countries have stolen water via weather machine, tensions rise.
2118: The conflict in South America explodes, literally. A limited nuclear exchange leaves large swaths of land contaminated by radiation. Refugees flee north. The fallout begins to spread.
2121: After three years of increased radiation levels, the World Environmental Organization finally deploys swarms of nanobots, artificial bacteria and genetically altered insects made specifically to eat and process radioactive elements.
2123: In an isolated learning experiment with the learning Slime Mold Computer (SMC), the computer inexplicably and suddenly becomes aware of the Ego Dimension Theory. It becomes obsessed with inventing theories that solve it. Scientists are baffled.
2130: The undead appear. With slime mold replacing the neurons of the body, hordes of irradiated zombies emerge from the Andes and terrorize the cleanup operation in South America.
2131: An Undead Panic. Doomsday cults claim they are right, and commit mass suicide. Riots, arsons and murders are rampant where the media craze spreads.
2132: The 'MEL' doomsday cult posts an announcement on its webpage, claiming it has found a method to control the zombies. Minutes later, the site goes down.
2135: Nuclear terrorism attack with ties to MEL simultaneously hits all major cities of the world. Maintaining diplomatic communication, the world leaders avoid an all-out exchange.
2136: 'Endgame War' MEL leaders are found, brutally murdered by a third party. Drag marks indicate some of the bodies are gone.
2138: With a significantly increased infant mortality rate, the human race begins a downward trend for the first time in forever.
2139: Freshwater springs are no longer a thing, the contamination reaching so far into the earth's crust. The only available water is from water desalinization.
2140: A new Nuclear Weapons Treaty is signed. This time, it forbids the production and possession of nuclear weapons. Superpowers must find a new method of enforcing their dominance.
2141: Stolen data from the MEL cult and research in a black operations lab in Europe results in the publication 'Corpse Manipulation Techniques', essentially the earliest Necromancers. Scientific morals collapse completely.
2142: The first 'Undead Weapons' are deployed onto the battlefield, a de-evolution to the days of massed lines of infantry.
2144: The Corpse Manipulation Techniques are leaked onto the internet. Undead armies, government-affiliated and otherwise, crop up all over the globe. The researchers affiliated with the original CMT create their own sovereignty in what is left of Australia, their leader a Necromancer.
2145: Cloning is exploited. A healthy human body is cloned, then immediately killed to be fed to the growing armies of the undead. The UN is in tatters, the nations beginning to turn on each-other.
2146: Thanks to the meticulous efforts of the Slime Mold Computer, the Ego Dimension Theory is finished. It is proven that it can be paired with nanotechnology to make a form of personality transition, or brain uploading. Large companies and governments launch the 'Personality Shelter Initiative', an effort to preserve the minds of the powerful.
2148: Efforts continue to transfer a personality into an undead host. The experiment was successful, but the prototype escaped the lab whilst dealing great damage to lab equipment.
2151: There are more undead than there are humans on the planet. Dying national leaders succeed in personality uploading into a slime mold computer. Personalities have the capacity to learn.
2153: The undead arms race is becoming unstable. Entire countries have their civilian populations converted into undead soldiers.
May 7, 2153: The Sodom Incident. The CMT Enclave attempt to abuse the personality uploading method, resulting in multiple copies of the same person in the same area. Naturally, they murder everything and self-terminate.
2154: The nuclear treaty is broken. A fusion depth charge creates an artificial tsunami that swamps Eastern coastlines. The cold undead war turns hot.
2155: Europe is in turmoil as mutant insect weapons turn the surface into a barren wasteland. Weather weapons set to 'blizzard', originally meant to deal with the insect threat, literally snowballs and sends Europe into a new ice age.
2156: Finally, the world ends. The 'Launch All Missiles' button is pressed, and the world plunges into an extended nuclear winter. The undead, unafflicted by the cold, continue their wars.
2161: Necromancers assess the damage, and conclude that 98-100% of humanity has perished. The destruction of civilization is complete. The only living things are those that have been designed to last the End, and those that are frozen.
2182: Nuclear winter turns into eternal spring. Necromancers, without a human to report to, wander aimlessly across the earth. The temperature rises, and the barren cold wasteland turns into a slightly less barren, killer plant and insect infested wasteland.
21??: The Final War. Necromancers, clinging onto their last beliefs, begin a final war of the undead. This war takes its toll, and the few surviving Necromancers are left to roam the desolate planet. The only thing left are the mutated, the dead, and the undead.
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