[To make things clear, this is obviously an A.U in which the majors powers of the Wasteland unify both theirs forces and technologies not only to rebuild Humanity, but also to claim the stars. I based myself on the basic Fallout lore starting from FO1 and FO2, but I obviously heavily modified this lore. Also, by the time Humanity discover the Mass Relay, they will have an extremely strong force, but I'll decide how strong it will be later. I also consider Element Zero less powerful than the Fusion energy used by Humanity in this Story, as no Council race ever discovered such power unlike Humanity. Humanity won't have it's ship size restricted by Element Zero, nor would it's ability to FTL be restricted by the Mass Relays, because the technological path Humanity went by is completely different! Also excuse me for the grammatical errors in my text, I'm not a native english speaker and I don't use any sort of dictionary nor translator to write my texts as fluid as possibles. If you detect some grammatical errors just leave a comment and I shall correct them.]

[!DISCLAIMER!: I does not own Fallout nor Mass Effect!]

[Heavily updated the timelines to fit Humanity finding the Mass Relay and founding Shanxi and many others colonies]

FO1/2 Era Ending: Death of the master, Destruction of the Enclave Oil Rig, but large amount of Enclave forces are still scattered around the Wasteland.

2277 and following years in D.C (FO3 Era Ending): John Henry Eden Supercomputer destroyed, Colonel Autumn surrender his forces to the Brotherood. All Eastern Enclave forces and technology are fully integrated into the eastern BoS chapter. The Brotherood of Steel later fall in the hands of the successor of Elder Lyon: Maxson. Maxson begin extensive recruitment program in the D.C wasteland, conscripting every genetically clean wastelanders they can and executing every ghouls and super mutants on sights, wether hostiles or not. D.C is transformed into a true bastion that the BoS entirely control, with High Tech artillery, hundred of Vertibirds and thousands of troops to protect it. An extremely large wall is constructed around Washington D.C to separate it from the outside world. Buildings are rebuilt, D.C is know as the "Old World Rising" town with even the largest towers temporally rebuilt with scrap materials. The Brotherood maintain large strongholds around D.C and it's outskirts, discovering ancients Pre-War bunkers all around the town. The largest one, codenamed Zone Zero by the brotherhood, is used as the new headquarter for Elder Maxson. Far more resistant than an Vault, and extremely large compared to any other underground structure under D.C, this bunker also support hundred upon hundreds of secret pre war military caches, armories, barracks, large supplies rooms filled with food, ammos, weapons, and all kind of stuff, even large supply of oil, probably the last pockets of oil in the World, as well as lot of Armored Vehicles and Vertibirds. The Brotherood even discover an ancient prototype which was supposed to be the successor of the VB-02 Vertibird before the bombs fell: The VB-03 Vertibird, an extremely resistant prototype with extremely powerful weaponries and hull made of extremely resistant alloys from before the war. But best of all, the Brotherood also discovered a gigantic Spacecraft buried in the bunker, an behemoth of an ship, larger than anything they had seen before, thousands times bigger than the Blimp that they were trying to build from scratch at Adams AFB. However, it wasn't fit for duty when they first discovered it and would require a lot of maintenance before being up and running. The gigantic aircraft was codenamed "Project: Fire Phoenix" by the Brotherood Scribe team. Aliens technology are discovered, the Alien Mothership Zeta is boarded up by an large amount of BoS troops after the Lone Wanderer advised Elder Maxson to "Check out that big ass alien ship I just liberated!". The BoS keep the secret of the existence of this motership and the existence of the Aliens for themselves. A few hundred of different types of mutants are secretly kept locked up in an old Pre War research facility, as the Brotherhood believe they could make powerful biologic weapons of them. Those mutants include some Deathclaws, Super Mutants of all kind (Including Behemoths), ghouls (Wether feral or not), giant ants and more types of mutants that the Brotherhood estimate to be deadly enough to be used as war tools. Lesser types of mutants, like Radroaches, are however completely extinguished, at least in the D.C wasteland.

2282 (NV Era Ending): Mr. House still alive and well in his independent New Vegas. NCR victory at the dam, NCR invade Arizona (Legion territories) and begin aggressive land colonisation, settlings farmers and settlements everywhere. NCR has the largest faction population at this time. The Western Chapter of the Brotherood of Steel has allied with the NCR and help them patrolling the Mojave and the surrounding regions, at the cost of the NCR giving up their few Power Armors and highly powerful technological devices. In a few years, the NCR-BoS alliance grab an significant portion of territory, at least 1 tenth of the whole American mainland. Eventualy, Mr. House and his securitron join the Alliance but does not actively participate in fights. The civilian population of the NCR controlled area count higher than the 80 millions. Any sort of raider gangs, deathclaw and other threatening mutants nests, and every hostiles Super Mutants and feral ghouls are systematically exterminated. Shaddy Sand grows up to such a point that, in term of population and length, could be comparable to some of the largest Pre-War Americans cities. The Western chapter of the Brotherhood of Steel discover 2 jewels of technology, Big Mountain and Sierra Madre Casino. Sending large groups of troops and scribes at both locations, they retrieve incredibly powerful and advanced technologies, like the Cloud, an extremely poisonous gas created in Big Mountain and tested in the outskirt of the Sierra Madre, Hologram Technology, including powerful security variants of such holograms, capable of taking down any ennemies with pure energy white not affected by bullets, EMP, radiations, nor energy blasts. The brotherhood also discover an area a lot of people's would know as "Area 51", an large Pre-War military stronghold holding hundreds, if not thousands of secrets that could greatly help the Brotherhood, including Zetan alien beacons and saucers, reverse engineered alien technological devices, large supply of Fusion core and an gigantic Fusion Core capable of powering up the whole world in electricity and energy. Due to the vastness of this place, the Brotherhood is forced to reveal it's existence to the NCR and to demand them to protect this along with their Knights while their scribes and scientific teams explore the darkest bunkers of that Area. The Brotherhood is getting an huge amount of different sorts of Technologies, and describe this as the most important discovery the Brotherhood ever made. They would be proved wrong later on, as the Eastern BoS discovered types of technologies that would surpass anything seen else before.

2287 and following years in Boston (FO4 Era Ending): Brotherood of Steel victorious -is but instead of destroying the Institute and massacring every Institute scientist, Maxson decide to keep them alive and their facility untouched. Synths programs are however shutdown. The Institute is integrated into the Eastern Brotherood of Steel. The BoS control a vast territory in the East and can now easily crush it's ennemies as soon as they show up. Massive conscription in BoS-controlled zones continue to take place. D.C population grows up in the Millions, and the town is literally in an almost pristine state, almost looking perfectly Pre-War-ish after the Brotherood began massive reconstruction programs on the skyscrapers and towers around D.C. The "Project: Fire Phoenix" spacecraft is almost operational at this date.

2288: The Brotherood of Steel has fully rebuilt the "Fire Phoenix" project Spacecraft, but keep it deeply into their Zone Zero bunker. The brotherhood of Steel has begun the development of extremely powerful energetic weapon, far more powerful than the ones they used before. New weapons like the AER-47 Infantry Laser Rifle (An extremely powerful, yet compact and versatile rifle capable of piercing an hole clean trough even the largest mutant in the Wasteland) and the Gauss Electromagnetic Assault/Combat Rifle [G.E.A.R], spiritual successor of the Gauss rifle developed before the war, are created. New types of Power Armors are developed.

2290: Elder Maxson leads an large Expedition toward the others Brotherood chapters, especially the Western Chapter, in an effort to tie their force again and take control of the whole country. High Elder maxson is accompanied by the "Sole Survivor", heroic BoS Sentinel from the Boston War, for this journey. A few days after their departure, first contact is made between the Eastern BoS chapter and the NCR in the West. The Brotherood also know how to control the Mothership Zeta, which is used as an mobile base command. However, even if the ship contain lot of technologicals devices that could be useful to the Brotherood, the "Fire Phoenix" aircraft, in essence, seem to be far more advanced than this mothership, as, after years of studying the aircraft, it was discovered that it was actually the very spaceship the U.S government was creating in the hope of evacuating Earth with the elite of the American society, and to colonise another world. The ship true name was also discovered, the "Enclave Star Colony Ship".

2293: At this date, the Western chapter of the Brotherood of Steel as well as every others BoS chapters are fully integrated into the Eastern Chapter. The NCR has also decided to unify with the Brotherood of Steel, and so did Mr. House.. Their Union was simply named "The Renaissance Union", as their primary goal were to preserve humanity as a whole, to preserve and develop new technologies, to take over the whole Earth, to remove any kind of mutants on the planet surface, and to accomplish an dream as old as the Pre War Sci Fi fans dreamt of: Space Colonisation. The TRU also discovered large amount of Enclave forces in Alaska and some parts of the mainland. The Enclave had large infrastructures in Alaska, especially in Anchorage, which they almost fully control. As no nuclear strikes ever hit Alaska's surrounding, this was the perfect location for the Enclave to base itself in. The Oil rig was only a phantom face of the true power of the Enclave. After a successful coup d'état led by an ambitious Enclave General against their former true leader, the biological successor of the Pre War U.S president, things drastically changed in the Enclave, and when contact was made with the TRU, the Enclave in Alaska decided to avoid war at all cost and to unify their force with the TRU. At this point, the Enclave also went on it's own technological path, with highly powerful Plasma, Laser and Tesla weaponries, as well as extremely powerful power armors and Plasma Powered Vertibirds.

2294: The Enclave forces in Alaska are now officially integrated into the TRU. The TRU is the most technologically advanced, and most powerful faction in America, and probably in the world. New power armors and weapons are issued to almost all TRU troopers. The TRU is now an Country-Like entity, with a central Government, a Military force, police force, agencies, and Industries fully operated by the TRU. At this time, America as a whole is completely under control of the TRU, and their leaders now turn their eyes towards the rest of the world, starting with South America and Canada. Meanwhile, the 'Zetans', previous owners of the Mothership that the BoS took over in the past (Which is now nicknamed as "Olympus"), came back near Earth with larger, more powerful ships. The Olympus was fully upgraded with TRU technologies in the past, and the Olympus proved itself powerful enough to destroy almost the whole Zetan fleet, thanks to both already present Aliens weaponries, but mostly thanks to the added up Humans weaponries, even if those were theorized to be more powerful than the Olympus. Apparantly, TRU wasn't the most powerful faction on Earth at this point, they were probably even more powerful than the Zetan. At this point, the TRU revealed the existence of the Zetans aliens to their population and mass conscriptions programs were made to recruit a maximum of soldiers fit for duty to reclaim Earth and fight back any sort of alien invasion. Colonisation of the Moon begins, with large Domes city built in Pre-War like shapes and structures. The Union begins the construction of large bunkers under moon surface in which they would storage their Nuclear weapons arsenal and their most powerful prototypes before they are fully operational. The Union is officially a space-faring entity. Also, thanks to Mr. House knowledge in Robotic technology, an large amount of different types of combats, maintenance, medical and others specialized robots are constructed in Union controlled factories and facilities, boosting up the Union military might.

2297: The Renaissance Union fully reclaimed all territories on the South American and North American continents, and Europe as well. Differents sorts of factions were discovered in those territories prior to their integration into the TRU, some were as powerful as the NCR was before the battle of Hoover Dam. An program is founded by the Renaissance Union Science Agency: the Earth Resurection project, aiming to fertilize Earth again, remove a maximum of radiations, and overall give the planet a second life, like before the bombs fell. Ex scientists from the Institute Bioscience division greatly help in that field. At this time, the Fire Phoenix was operational and was already in orbit around Earth, thanks to this beast of technology, the Renaissance Union could quickly take Earth back, and could also repell Zetan invasions fleets if some ever came back. An large Zetan facility is discovered on Mars, on which the Zetans were creating hundred of spaceships to invade Earth. Their facility was taken over thanks to the Olympus and the Fire Phoenix. The battle for the martian facility was also a way to introduce the newest power armor in the Renaissance Union pockets, the SPARTAN power armor as well as many sorts of weaponries. The facility is taken over, and it is technically the first off world facility of the Renaissance Union. The Union use this facility to construct more ships thanks to the resources already present on Mars. Project "Behemoth" is initiated, to create an massive scale ship, even LARGER than that of the Fire Phoenix ship, to colonise another world and annihilate the Zetans fleets and home world. Hundred of bunkers were built both on Earth and Moon in years following the destruction of the second Zetan fleet. The moon is lighted by Domed Cities everywhere on it's visible surface. A lot of technological innovations are made. The gigantic Fusion Core, also known as Project: "Light in the Darkness" is now functional and power up every Union territories. Schematics of the core are taken to Moon in an effort to eventually mass produce those cores in light of Space Colonization, giving the Union almost infinite amount of energy to boost up their force.

2299: Earth is almost fully reclaimed. Thanks to extreme technological enhancement in term of bio technology, most of the TRU owned territories were "resurrected", with vegetation and even wildlife created in laboratory, spanning everywhere on TRU territories. The only remaining parts of the planet not under Renaissance Union control at this point were a few Asians countries, including China and the Siberian regions of Russia. The human population on Earth surpass 4 billions at this point, at least in TRU controlled territories. The TRU Leader, Maxson, hesitate to take over China as it was hit by the most powerful Nuclear warheads of the U.S.A, not only that but Bio Weapons were also used against the chineses towns, especially an specifically horrible strain of the F.E.V. Maxson believe that controlling China would be impractical as the fertilisation of the area would be impossible and because of the large amount of mutants in the region. Maxson decide that it would be a waste of resources to do so, and order the construction of gigantic walls around the now called "Black Zone", also known as China to prevent any sort of mutants lifeforms to invade the rest of the world. The Science Agency of the Union discover nanotechnology and perfected the forcefield technology as well. Most of the Union technologies relied on Fusion energy, the Fission being outdated by then. Larges parts of the Moon were terraformed and bio-engineered wild life were introduced in this new environnement. Mars is being terraformed as well. The extremely ambitious project, "Behemoth" is almost fully completed. Every technologies retrieved by the Union in the last years is added to this ship, in an effort to create the perfect, indestructible and extremely powerful Behemoth, capable not only of bringing millions of people's to another planet and to terraform such planet, but also capable of taking down entire Zetan fleets easily. The Zetan home world is discovered near the Zeta Reticuli system. Union forces maximize the production of their gigantic High Tech armada of ships. In the late 2299, an Union well known scientist discover the Microprocessor technology, which is an extremely important technological discovery of the Union, permitting the creation of sophisticated computer systems and hardwares. However most Union computer tech, even if they are now extremely advanced, keep a part of "Retro" touch.

2300: 233 years after the bombs fell, in the 24th Century, the leader of the Renaissance Union makes an historic speech in his command base, Zone Zero. "People's of Earth. I am you're leader, you're guide. I am Maxson, Director of the Renaissance Union, formed of the former forces known as the Enclave, the Institute, the New California Republic and the Brotherood of Steel. And today, if you can listen to this speech thanks to the TRU-issued radios and communications equipments, it's because we have finally accomplished our rebirth. Our revival! Today, the whole world, excepted for a few places that no one should go to, has been taken back from the radiations, from the mutants, from the devastation and from the madness of man. Humanity is no longer struggling for survival. Humanity is now more united than EVER before! And in a few days, we shall select brave citizens of the Union to go on an epic adventure trough the STARS! Yes, brave people's of Earth, despite all the obstacles, all the difficulties we have went trough, we can finally say it loudly: We are ready to look toward the mysteries of Space, we now officially begin our Space Colonisation Program! As our initial goal of Renaissance has been already achieved few years ago, I permitted myself to change the name of our Union. We are no longer the Renaissance Union, we are the Terran Federal Union, a worldwide nation with colonies away from our mother Terra. We are strong, we are united, we are the Terran Galactic Union, and we shall never repeat the errors of the past which provoked the Apocalypse. We must not forget our history. Remember that yesterday, you slept in barely protected shacks made out of scrap metal, barely surviving, cultivating mutated crops and fending off mutants, but today, you sleep in luxurious apartments all over the world! There is an old statement claiming that 'War never changes'. And let me tell you, that is true. And we shall never again fight each others. We shall no longer self destruct our specie. However, war is a necessity against outer threats. As you probably already know, an alien specie known as the Zetans are constantly attacking us, but they are weak compared to our forces. We shall protect our world, our mother: Terra. We shall continue to develop technologies in a way to enhance our lives. Terra shall live forever. Ad Victoriam, citizens of the Union! AD VICTORIAM!". To victory. In unison, the world yelled "Ad Victoriam". Because humanity was indeed going to victory. After triumphing from it's darkest era, Humanity was ready. In the days following this ambitious and historical speech is a new era of hope, discoveries, mysteries, and after the Renaissance, humanity shall rise from it's ashes.

2321: The Terran Galactic Union, 21 years after the historical Speech made by Director Maxson, has colonized 102 worlds, some of which are really well developed, and fully terraformed Mars and the Moon. The Zetans forces were crushed on their home world only few hours after the Behemoth jumped into FTL to assault to their world. The Behemoth simply took down a whole specie naval force with ease thanks to extremely advanced Forcefield technology powered up by a massive Fusion core, as well as it's extremely thick and resistant hull made of an alloy more resistant than Titanium and Diamond. The Zetans home world was nuked with extremely radioactive F.E.V-filled Nuclear Warhead all around their towns. Any sort of escape ships were destroyed by the Behemoth. Following this, a few Lyons Class Destroyer were deployed around the planet to quarantine it. The Zetan home world is now used as an testing zone for various biological weaponries Humanity possess. The irony of this being that being that the Zetans were the actual ones doing this on Earth before the Union rose up to power. At this time, the Union ships are nearly impervious to damages, especially the Behemoth. The Protean base on Mars is discovered and investigated by an Union force, at first thinking it is simply an Zetan observation facility built before the Union rose, they were proven wrong as they discovered technologies of another type, including Element Zero. After long months of studying the facility thanks to the best scientists of the Union, it is discovered that a race named as the Protean were using this facility to observe Earth even before the Zetans arrival. The Scientific team consider it a bit strange because of the fact that their technologies, even Element Zero, seem to be rather primitive compared to theirs. The location of the Charon Mass Relay is discovered. The whole Earth, including China, is radiation and mutant Free. Extensive F.E.V and biologic weapons experimentation begin. An gigantic robot factory is created on the Moon, supervised by Union forces. Mr. House chamber is transported into the deepest bunker on the Moon and completely locked away from the outer world to protect his body from being destroyed. Mr. House is apart of the Union Directorate, while the former elder of the Brotherhood, Maxson, is the Head Director of the Union. The Union Institute of Technology is created on Mars, in which the highest minds of the Union works days by days to perfect the current Union technology, especially the military one. After years of begging to the Head Director Maxson, "Father", former leader of the Institute, now in the same state as Mr. House is, obtain the permission to re-start the Synth project under extreme supervision by Union troops. It is forbidden to create synths identical to humans beings anymore, however it is authorized to create synths capable of the same tactical and fighting skills as an lambda Human Union soldier. Those Synths are dubbed "Generation 4 synths", despite technically being a bit less advanced than the Generation 3. Union Scientific Agency work hard days by days to create the perfect A.I, completely harmless to humanity and without any possibility of Rebellion against their creators, but extremely powerful in combat against non-humans species. The creation of Humans Super Soldier is re-launched again, but unlike the traditional Super Mutants, the Union Meta-Humans have human skin color, level of intelligence and looks. The only difference with a standard human being their extremely increased musculature and physical force. The Meta-Human corp is created along with the Synthetic Corp. Experiments to transform the primitive death claws into extremely intelligent killing machines begins on the Martian Union BioGen Labs.

2322: The Charon relay is protected by a small detachment of the 21st Union Fleet. The relay is deemed too primitive to be used as an mean of FTL, the Union leaders preferring the more versatile, less costly and yet more powerful version of their FTL using Fusion Core. Element Zero is considered far less powerful than the Fusion energy. However, the Union order a small Investigation fleet with built-in EEZO cores, to go trough the Relay and report any alarming informations about what is on the other side. The investigation fleet discover the planet of Shanxi and another Mass relay not so far away. Experiment on Psychics powers begins thanks to intel gathered about the psychological effects of the Forced Evolutionary Virus. The Psyker Corp is created, counting only a few hundred humans with powerful psychic mental powers. Testing with the Deathclaws are positives and encouraging, as several death claws, after exposure to a special strain of the F.E.V. can now be considered as intelligent as juveniles humans. Their use on the battlefield is evaluated.

2333: The Colony of Shanxi is founded. An tentacular city, Diamond City, is founded as the Capital of this colony, but the true nature of the Union operations on Shanxi is to create a massive Military garrison between the 2 relays incase the primitives species, especially the Proteans, try to come back using the Relays. Total Union human population surpass the 300 billions thanks to extensive propaganda to make sure the population reproduce heavily, as well as thanks to a massive use of DNA cloning. The Meta-Human and the Synths can only be counted in the few millions however, as they are exclusively used for Military tasks. The Head Director of the Union is placed in cryogenic chamber and his mind join that of Father and Mr. House, creating an impressive collective of minds. The 3 are designated as "The Brains of the Union". Unknown to all, the Courier and the Lone Wanderer are also stored in a cryogenic facility. A new Head Director is chosen, and it is the now the 73 years old "Sole Survivor" which is chosen for such a task (He was 27 years old when he went out of the Vault 111 Cryo pod by the time of Fallout 4). His physical body will stand for several more years until it would be to weak, and at this point his brain would be placed into a biologic, physical copy of his younger-self. The Sole Survivor is dubbed as "The Director", an shadowy figure which few people's really know.

2337: "The Director" is transferred to his physical, biological body synthesized in the U.I.T. More colonies were created. Technological advancement of the Union is moving in a straight path to perfection.

January 2343: Captain Alexander Autumn is patrolling Shanxi while an Investigation fleet is studying others Mass Relays. Our story start there.

[Please leave feedbacks, as if people's appreciate my fanfic and actually show this appreciation, I'd be more motivated to write more of this. I played every Fallout games but Tactics and Brotherood of Steel, which, anyway, aren't lore friendly, but I decided to change quite a few things in the base lore to settle my story. I also resumed the FO1 and 2 ending quite vastly, but I didn't have much to say about that. If you are wondering, not all Super Mutants or ghouls are being killed without exception, in fact the Union got several researches facilities in which those mutants are kept locked in, and experiments are made on them in an effort to make powerful.. mutant soldiers. I updated the timelines to include stuff like Big Mountain from Old World Blue FNV DLC and Sierra Madre from the Dead Money DLC.]

[I shall introduce the CODEX in the next chapter so I won't start directly. Please leave feedbacks and suggestions about which Mass Effect specie should discover the Union investigation fleet first. I wish to begin with a First Contact War so far but I know the Turians were overused in previous Fallout-ME XOver.. Leave me suggestions please :)]