A/N: I can't stop righting new fanfictions, and I am sorry for that, but I am just doing this for fun, so let's give this a try shall we, oh yea and by the way this will only be the timeline for now, bye-bye.
Human Timeline
2277: The First Battle of Hoover Dam takes place. Caesar's Legion forces under the command of Joshua Graham attempt to take the Hoover Dam from the NCR. Although the attack is initially successful, the NCR lures the Legion into a trap and sends them retreating. Most of Boulder City is reduced to rubble in the battle. Legate Graham, deemed responsible for the defeat by Caesar, is coated in pitch, lit on fire, and tossed into the Grand Canyon to set an example for others.
August 17, 2277: James disappears from Vault 101 and his son, the Lone Wanderer, heads to the surface to search for him.
James, the Lone Wanderer's father, sacrifices himself at Project Purity to thwart Colonel Autumn's attempt to commandeer the facility for the Enclave.
The Lone Wanderer activates Project Purity, declining the Enclave's request to sabotage the purifier, and the Capital Wasteland is changed forever. Adams Air Force Base is also destroyed. The East Coast Brotherhood of Steel begins to distribute Aqua Pura to a thirsty Capital Wasteland.
2278: The Earth is saved by the Lone Wanderer from an alien threat when they are captured in the northern Capital Wasteland by an alien mothership named Zeta, taking the control of the ship with a typical group of survivors from Earth's past.
Elder Owyn Lyons of the East Coast chapter of the Brotherhood of Steel dies of natural causes and is succeeded by his daughter Sentinel Sarah Lyons. This does not last long as she is soon KIA and a succession of ineffectual leaders attempt to lead for several years.
2280: The Brotherhood of Steel send their first recon team to the Commonwealth. The mission is a success, with the team returning with information on the region and other important assets.
October 11, 2281: The Courier is ambushed and shot in the head by Benny, left for dead in a shallow, unmarked grave in Goodsprings Cemetery. Victor finds her body and retrieves it, and the Courier makes a miraculous recovery in the care of Doc Mitchell
October 18, 2281: The Courier regains consciousness and leaves Mitchell's house in Goodsprings for search of revenge against Benny.
October 20, 2281: Benny is found dead in his apartment, the culprit was never found, but it was suspected that the Courier was responsible.
2282: The Courier takes control of New Vegas, after the battle at Hoover Dam.
February 3, 2282: New Vegas now encompasses Big Mountain, The Divide and Zion.
2283: Following his successes as a Knight in the East Coast Brotherhood as well as possessing a strong will and a knack for diplomacy, a sixteen-year-old Arthur Maxson is promoted to Elder and given command of the East Coast Chapter. He continues his impressive career first by recanting several of Owyn Lyons initiatives including the protection of common wastelanders in favor of collection of technology and reconnecting with the West Coast Elders which brought the Brotherhood Outcasts back into the fold and bolstered their numbers.
2287: The Quincy Massacre occurs. Gunners destroy the town and kill all but 20 settlers. A squad of Commonwealth Minutemen attempt to defend the town but fail. Sole surviving Minuteman, Preston Garvey, leads surviving settlers away.
October 23, 2287: The Sole Survivor leaves Vault 111, exactly 210 years after the start of the Great War in search of their son Shaun.
October 30, 2287: The Brotherhood of Steel and Elder Arthur Maxson arrive in the Commonwealth from the Capital Wasteland, with Boston Airport being secured and set up as a regional base of operations, leaving the Prydwen in hover mode above the airport. Vertibirds begin to patrol the skies, and research patrols and ground teams carry out operations throughout the region.
2289: The Sole Survivor becomes the general of the Minutemen, leading them to victory against the institute. The minutemen take control of, all of Boston, and began expanding into Far Harbor and after freeing the slave's and killing all the raiders, Nuka World.
2290: The three powers, the Commonwealth, New Vegas and the NCR have summit at the Lucky 38, to discuss their borders.
December 22, 2290: The borders are decided, New Vegas got Arizona, New Mexico, Texas, Oklahoma, Utah and Colorado. The Commonwealth got everything east of the Mississippi river. The NCR was given everything else in the former United States minus Hawaii and Alaska witch where decided to be a shared zone.
2291: The population of the NCR has reached 100 million, while the Commonwealth's population isn't far behind at 70 million, and behind them is the smaller nation of New Vegas (46 million).
January 20, 2291: The Brotherhood of Steel are assimilated into the Commonwealth becoming the military branch of the Commonwealth along with the Minutemen.
March 12, 2291: New Vegas assigns the Think Tank their first major objective since the Great War, design a more maneuverable and light weight power armor.
August 17, 2291: The NCR have rebuilt the steel plants in the pit and have begun producing steel for the first time since before the Great War.
August 21, 2291: The 'Think Tank' has created a new version of power armor that is smaller, more maneuverable and only weighs a fraction of the older models it is dubbed the Z-02 power armor.
July 20, 2292: As a sign of friendship the Commonwealth lets scientist from Big Mountain and the NCR examine the two-alien space ship's they discovered.
August 3, 2292: The Commonwealth Brotherhood has sent scouts over the Atlantic to see if their where any survivors in Europe, the whole crew where disappointed to see nothing but skeletons.
January 24, 2295: The Space ships have been reverse engineered by the 'Think Tank' and a prototype starship has entered the testing phase.
2296: The Prototype star ship was a success and was named 'N.V.S Hope' exploration of the solar system has started.
April 17, 2296: structures are detected on mars, the scientists on board are sent down and they retrieve a strange message in a language they had never seen before. The message is sent back to 'C.W.S Zeta' (Mothership Zeta) the computer on board the craft was able to translate the language to English the message was a warning "the Reaper's are coming."
April 18, 2296: The 'Big Three', the leaders of the three nations, gathered once again in the Lucky 38 and discussed what to do about the message.
April 21, 2296: after three days of deliberation the three nations decided that they needed to build a stronger military and explore the alien ruins on mars thoroughly.
May 7, 2296: The NCR launch their first ship 'N.C.R.S Kimball' named after their first president.
August 28, 2296: The mars exploration team has unearthed what looks to be a warp drive, the team sends it back to the 'Think Tank' for further study.
2297: The 'Thank Tank' have unraveled the mysteries of the alien artifact and pronounce it to be a warp drive capable of moving a ship at faster than light speed's. The Courier made the production of the device Big Mountain's main priority.
February 2, 2297: The 'Think Tank' Discover that the material that powers the warp drive is one that can't be found in their solar system, they begin to study the atomic structure of the element for synthesis later.
November 26, 2297: The 'Think Tank' successfully synthesizes the mysterious element and name it Element Zero or eezo for short, the material was named after its main property, it lowers the mass of the materials around it making it extraordinarily useful for space travel.
January 15, 2298: The first element zero drive is complete, and it is installed on 'C.W.S Zeta' as a gift. Later human ships would have both an eezo drive core and a Zeta drive core.
February 2, 2298: The Mars research team have discovered that Pluto's moon Charon is a large structure designed for FTL transit.
February 4, 2298: The ship 'C.W.S Zeta' is sent through the newly dubbed Mass Relay, after returning several hours later it is discovered that it leads to the Arcturus Stream.
February 9, 2298: The Big Three meet at the Commonwealth capitol, Sanctuary to discuss their next plan, it is decided that they would create a space station at the other side of the Relay.
2300: The population of earth is now 500 million and rising every day. The fleets above earth now number in the thousands but there are only a few Zeta class ships which are at least a kilometer in diameter, the largest being 5 kilometers in diameter, unfortunately there are only three of that size, those being the flag ships of each nation.
2302: using the G.E.C.K the earth is now free of radiation, and transforming on the moon had begun.
2303: The moon is now habitable and has a large colony with a population of 1 million.
2308: Arcturus station has been completed and it has its own dedicated fleet and the mothership 'N.V.S Lucky 6' as its guard.
2320: The population in the sol system is now 1 billion and the technology has finally surpassed that of the old world.
2321: All ships have been equipped with mass accelerator cannons, and most larger ships have a 'Death Ray' as their main gun, because of how much more powerful it is in combat.
2322: The big three have one last meeting at Shady Sands to discuss unification. They decide to unify their respective governments and the new government is christened 'The Systems Alliance'.
May 4, 2322: The colony of Terra Nova is founded.
July 18, 2322: The colony of Eden Prime was established
2323: The 'Big Three officially step down and let the Systems Alliance parliament take control of all assets.
2230: The systems alliance green light the activation of Relay 314.
March 23, 2230: A small flotilla of three research ships' is sent to the Relay. Upon arriving the flotilla is shocked to see a fleet of unknown origin, thinking quickly the captain sends the first contact package. The alien ships fire upon the research flotilla, destroying two ships and badly damaging the third before it could escape through the Relay to the safety of Shanxi.
A/N: I feel like I need to clear some things up, the Humans can create element zero and that means normal restrictions on size don't apply. The Humans didn't colonize mars because of paranoia, the same reason that the number of ships they have is even larger than the migrant fleet. The timeline is kind of messed up because of fallout, but I'm just going to ignore it. If you want me to clear anything up for you just let me know. I hope you liked it Bye-Bye.