There were many names for that year, Heisei 27, Juche 103, Year of the Commonwealth 239. We know it as 207 B.V. In September of that year, the world ended. We don't remember why it happened, but we do remember it was our fault. A night fell upon the planet, all because we refused to think about the consequences of our actions. We didn't want to end, we didn't want to be forgotten. In those days before the world ended, we sent billions of tiny blobs of cells out into the cosmos. With them, we sent all they would need. Food to sustain them, buildings to house them, and robots to teach them. But there was one thing we didn't send.
Parents to raise them.
Perhaps it was our intention, perhaps it was an accident, or perhaps we simply couldn't. The reason no longer matters, all that matters is what that action has made of us. On countless worlds mankind now blooms, guided only by the beliefs, prejudices, and values of those who sowed their seeds. Each seeded world is a nation in itself, built upon that which was taught to those who first emerged from the incubation chambers. Each nation follows it's own ideology, a distilled form of that which they who seeded the cosmos wished to preserve. Brainwashed from birth, they built proud new civilizations on these faraway worlds.
While they lived in paradises built for them by their iron servants, we wallowed in radioactive filth on the homeworld. We watched as the dust blocked out the sun, we wept as we strolled through the ruins of our cities, we starved as the plants withered. But we survived. We ate the rotting carcasses of animals and our own dead brethren and packaged food. When those ran out, we turned to the oceans. Practicing chemosynthesis, a new kind of producer had emerged as the base of the Earth's food chain. We survived on the sea's bounty, eating every last part of every last animal we caught.
That was when the cities returned. At first it was just tribes living in the ruins of port cities, but it soon became much more. New buildings of wood and stone appeared for the first time as we flocked to the ocean, the only thing that sustained us. The giant ships that had once sailed between continents became oceangoing cities, full of nomads scouring the ocean for prey to eat. After decades of this lifestyle, the dust cleared. At first it was just a dim twilight that told us how the days went by, but soon it became something we had always dreamed of. In approximately 180 B.V, we saw the sun again. The nightmare was over.
Those who had been lucky enough to find a place in the underground shelters emerged with their frozen seeds, plants, animals, and technology. The world lived again. For almost two centuries we rebuilt, adding to the floating ones. Fleets of city ships came together, each ship specializing in a different trade. Hydroponics from the survivors underground let us eat plants once again. We knew a life more comfortable than we could have dreamed of, all of the health problems caused by eating only meat eliminated.
Then they came.
It all started somewhere in the Pacific, aboard one of its many city fleets. The radar on the old military aircraft carrier that was now the fleet's garden ship detected a fleet of ships that had appeared out of nowhere. Assuming it was another city, messages were sent to it, asking for its name. There wasn't any response, and the citizens of the fleet could do nothing but wait for their arrival.
The ships were like nothing we had ever seen. Glowing lines criss-crossed their hulls, and they had giant turrets on them just like the battleships of old that could be found in a few of the city fleets. Some of them flew just above the water, kept above it by some unknown force. The largest of them moved to dock with the fleet, and nobody resisted. They didn't know what was to come.
Out of the ships poured soldiers, brandishing weapons far more advanced than anything we had ever seen. Odd vehicles, some floating, some walking on mechanical legs stormed the fleet with the soldiers. An SOS message was all that got out, reporting a hostile action and the location of the fleet. It was unheard of for a human to kill another human, everyone was surviving together. We hastily brought together a force of ships and planes that had been used for war before the world ended, repairing then as quickly as we could before sending them out to meet the enemy. The weapons of antiquity were no match for the invader. Everything we sent at them was shredded by their force, the only survivors were those that fled before reaching the thick of the battle. Though we lost the battle, the city was saved.
The inhabitants rose against the invaders, and smashed the two fleets together. Locked together by the rebels, the soldiers on the fleet that had appeared out of the fog and the inhabitants of the city clashed. Weapons were stolen from the occupying force on the city fleet itself, and they fought their way outwards from the epicenter of the rebellion. A communications room was captured, and they sent out a signal to the rest of the world once more. The world responded.
All the city fleets of the Pacific and Indian Ocean flocked to the battle, docking themselves with the allied fleet and sending their own people into battle. Factory ships began to build weapons for the soldiers. It was a ragtag resistance, and very few knew how to properly fire a gun. As a result, a myriad array of weapons was used. Melee weapons like halberds and swords were popular sidearms, while submachine guns utilizing drum magazines were a popular choice due to their ammo capacity. Captured energy weapons, however, proved easiest to use. There was no kickback, and seemingly no need to reload them.
The invader ships were captured, and their crews slaughtered. Our worst fears were confirmed when we took of the gas masks they wore, revealing their very human faces. A search for their homeland was initiated, planes from the countless different cities scouring the Earth for where they had come from. The disorganized effort never found anything, and the attacks continued. It had turned into a war, and nobody knew where the enemy had their economy.
That was when the three rose to power. They were from a city fleet in the Bering strait, which had been inconsequential aside from exports of whale products up until then. One of them (the leader of the fleet) called a meeting on the fleet's flagship. The other cities involved in the war sent delegates, intrigued by the out-of-nowhere proposal. The three (Two men and one woman) made a seemingly insane proposal: unification of the cities under one government. Through this, they claimed, the war could be won.
With little other choice, the cities agreed. The three made themselves the rulers of humanity, and just mere weeks afterwards it was announced that their city had reestablished contact with the old spy sattelites from before the war. Using the orbital cameras, they scoured the Earth for any sign of the enemy. Nothing was found, but their fleets were observed appearing out of nowhere into the middle of the ocean. Many battles later, we learned to predict their arrivals and counter them. Captured and reproduced ships destroyed their fleets the moment they appeared.
The enemy launched a final offensive, bringing an entire world's worth of naval warships. It was something we had all expected, foreshadowed by a silence before the coming storm. The city fleet that now served as humanity's capital was waiting for them, alone and with only a handful of ships.
Nobody knows what happened next. Some say there was a great battle wherein our forces destroyed a vastly overwhelming enemy, others say orbital weapons were used, and yet more tell of chemical weapons. There are even legends about a nuclear missile being used, but whatever happened, the enemy was slaughtered. A great attack ordered by the second of the three leaders destroyed the majority of their fleet, leaving only a few ships that were boarded and captured. There has never been another attack since.
The three were hailed as heroes, and continued to reign as the leaders of humanity. We expanded our cities, built up armies to fight off any future incursions. We settled cities inland, repopulated towns that were left untouched by the nuclear bombs. We even reached back up into space, exploring the planets and their moons. We had reclaimed our former glory, and perhaps even more.
The three leaders unveiled a new technology, reverse-engineered from the ships captured during the war. It was a device that allowed us to send people and objects between universes. It was believed to be what they had used to invade, which seemed to confirm the origin of the enemy in an alternate reality. Tests came immediately after its creation, and after dozens upon dozens of attempts at finding uses for it, they stumbled upon a universe where distances seemed to be compressed.
Obsessed with the idea of traveling to other stars, the third leader ordered spacecraft to be fitted with the device and tests to be performed. Many were lost simply gathering data on how to keep a vessel safe in the other universe, as the third leader refused to wait. It paid off in the end, and humanity's first starship returned from the universe a year later. It reported that it had reached the system of Kepler 22, after extensive guesswork on how distances corresponded to each other. The data on the new interstellar engine was sent out into space on robotic starships, in the hopes that the seeded civilizations would return to their homeworld.
It has been a year since then, and the current date is 92 A.V. (After Victory). As one would expect, it has been 92 years since the climactic battle for our continued existence. The other humans spread across the cosmos will be receiving the messages soon, and the third leader has made sure that he lives to see that day. Advanced medical technology has eliminated the degradation of cells as they split, and though it is expensive, the cellular therapy is periodically given to the three leaders to keep them eternally young like a technological Fountain of Youth. They still reign, for the people have not forgotten what they did in the past.
Only time will tell what lies ahead
Well that was long and unnecessary. So, since none of you read that, here's the TL;DR version:
-A nuclear war happened -We seeded other planets with population bombs and sent robots to teach them, which inevitably resulted in a bunch of ideological groups creating entire civilizations that are brainwashed to conform to their beliefs. -Earth rebuilt over time -Earth was invaded by a civilization from an alternate universe, igniting a war that was won 92 years ago -Reverse engineering gave us an FTL drive that's basically just hyperdrive from Star Control. -We sent out starships carrying this information to the seeded planets, because we love to play with the stuff Prometheus gave to us.
So yeah. The focus here will be on how the ideologies of the human civilizations interact, though alien nations may be allowed if enough people yell at me to include them. If everyone hates this idea, it might evolve to the point that it isn't recognizable. Which is great, because stories generally tend to change for the better over time.
There WILL be a "Big Bad" in the form of the nation(s) from other universes. What wasn't explicitly said in the Long and Unnecessary History will be said here: -There are multiple (Three as of now) such nations, and they're all somehow screwed up. -They all control multiple alternate versions of Earth and other planets -They didn't just forget about this universe -They know about each other -And they all hate each other's guts
This is pretty much just here to see if anyone is interested in this general idea, and please, scream at me to point out massive gaping flaws that I'm SURE exist. Because if I don't know about them, I can't fix them, and if I can't fix them, this can't ever take off.