Author's Note: This is set in the 1960s. As such, many characters use language that is highly offensive by 2019 standards. To censor this would compromise the historical basis of the story. You've been warned.
Chapter 1 - Gimme Shelter
March 5, 1968
Unknown Mass Relay, Unknown System (PLANET COUNT: 8)
It was the worst punishment the Migrant Fleet could ever bestow on one of its own. A sentence carried out only for the most severe of crimes - crimes that could actively endanger the existence of the Flotilla itself. It forced those quarians expelled in such a matter to fend for themselves in a galaxy that had grown to view them with disdain, and without regular immuno-boosters they would eventually be confined to those accursed suits full-time, without even the occasional luxury of getting out.
And now the entire quarian race had been handed down that fate. Again.
Admiral Neel'Koris vas Relnara reflected on the events of the last few years as the Migrant Fleet made its long, slow trek through the newly-activated relay. Apparently this relay had been encased in ice next to a planetoid, and its activation had done something strange to the planetoid's orbit. He hoped all would go well here, as it seemed everything that could go wrong for the quarian people had gone wrong lately.
It had all started with Keel'naha ("Distant Home"). The frozen, high-gravity world had been discovered by the Quarians as they were chartering The Rising Massing, the only world orbiting the newly christened star Salahiel. It was freezing in all areas except a relatively narrow part of the equator and had crushing gravity…but it could work. After over a hundred orbits of Rannoch around Tikkun, the flight from the homeworld had gone on long enough for everyone. Some factions in the Migrant Fleet had been arguing for a reclamation of Rannoch, but there were enough colonization advocates that significant resources had been poured into exploring star systems - enough to find Keel'naha.
Grimly, Neel'Koris reflected that he had been one of the strongest colonization advocates, and wondered how much of the blame he shouldered for what had happened afterwards.
A minority on the Admiralty Board argued for approaching the Citadel Council and asking for colonization rights. But three of the Admirals had countered that the Council would never allow them to settle a world, and the only viable course of action was to gather in this system and build the colonies up, biding time until the Council found them.
In the end, it took about a year. In another timeline, the Quarians would have left quickly. But in this one, they had been settling the equator for quite some time and had begun the process of turning Keel'naha into a home in earnest. When the Council renamed the world Ekuna, gave it to the elcor, and demanded they leave within a month, they stood their ground. They warned the Council that Keel'naha was their home and they would fight to defend it.
Of course, what the Council didn't know at the time was that the Admiralty Board had to unanimously override a (narrow) Conclave vote in favor of abandoning Keel'naha, as the Conclave was terrified of the prospect of war with the Council. In accordance with the law, all Admirals had then resigned, which was how Neel'Koris had gotten his position. His first few weeks as an Admiral were spent frantically hiding the liveships and preparing for war.
In the end, they surprised the Council. They had managed to take out six dreadnoughts and several hundred smaller ships before sheer force had overwhelmed the Migrant Fleet and their colony and they had surrendered. The war had cost them nearly 5% of their population, a devastating blow for an already thinly numbered and close-knit people.
The main reason Neel'Koris had kept his job despite the utter defeat in the Keel'naha War (or the Ekuna War, as the now elcor-owned planet was called) was the display he had put on for the Council afterwords. In chains and expected to beg for mercy, he instead decried the Council as bloodthirsty imperialists who were no better than the Batarian Hegemony. An enraged Councillor Terntus had demanded the destruction of the Rayya as punishment for the quarians' defiance, but Councilor Nelyana had talked him "down" to exile.
As the Relnara continued its introductory scan of the new system, the last words the Councillors had said to him rang through his mind.
"The quarians have proven themselves unable to follow and abide by the laws of not just Council space, but all of known space. And so the quarian people are hereby permanently exiled from galactic society. All Migrant Fleet residents and pilgrims within Citadel Space will be escorted to Relay 314 within two weeks. When you are gone, we will take the unprecedented step of destroying the Mass Relay behind you, as to ensure that you may never return."
"But…Councilors, this is barbaric!" He had tried to scream, but it came out as a whimper of protest, which Terntus seemed to enjoy. "You chose this fate for yourselves when you failed to leave Ekuna," he had said. "Perhaps the unknown will contain a planet for you. It doesn't matter to us. The quarian race is no longer welcome in the chartered regions of the galaxy. Go, and NEVER return!"
And so he had been taken away, and the nightmare had began. Every quarian that could be found was dragged back to the Migrant Fleet, including the exiles (they were kept in a prison ship under constant guard). The Terminus Systems even got in on it at the behest of the Council - the Batarians sold back their quarian slaves at a high price, perfectly fitting the Ancestor saying "Misfortune let us to this fortunate meeting." And on the appointed day, the quarians were forced into the unexplored relay, which was then destroyed (at a safe distance) at the cost of two of the nearby system's gas giants. There was no way back. They were truly alone.
Neel'Koris' depressing musings were interrupted as the ship's VI sounded off an alert.
"Radio signals detected. Language unknown. Estimating technology level of newly discovered race."
"Keelah…" So this was it. They had been traveling through the unknown for months on end, desperately trying to find a vacant dextro-amino protein world. They had encountered a surprising number of uncharted garden worlds, but all were levo-amino based. And so the Migrant Fleet continued searching, and continued finding empty levo worlds, until…
"Analysis completed. Inferred planet designation: 'Earth', 'Terre', or "Dìqiú". Radio signals and satellites consistent with Level 3 Non-Spacefaring Race."
"We found a pre-spaceflight civilization!" One of his ensigns shouted. "Ancestors, we could uplift them! Use them to find a way back to Council space!"
"Don't get ahead of yourself, ensign," the Admiral replied. "Unless the scans are off, this is likely a levo-amino based planet. Not to mention that their astronomers can probably observe us, which means the sight of 50,000 ships coming towards their world is likely to scare them."
"Should we even bother?" Another ensign asked. "If it's not a dextro world-"
"We're running out of relays to search, Barri'Ortus. Relay 314 was the only one we know of that linked back to known space, and we're starting to hit a wall on discovering new ones. Perhaps this new species can help us."
Over the following weeks, as the Migrant Fleet edged closer to Earth, various observatories throughout the world noted with alarm that a large swarm of unknown celestial objects had caused a bright flash near Pluto and appeared to be rapidly closing in on Earth. Governments tried to censor the information at first, but as the Fleet grew closer amateur astronomers and the press put two and two together. By mid-May the ships had grown in the sky to the point where it was impossible for even dictatorships to BS about it, and by June a tense waiting game began when the first quarian ships made their way into Earth orbit.
In retrospect, many humans would remark that the quarians picked a really bad year to make First Contact.