Hello fans of halo and mass effect, I always wanted to see how this would play out if the human-covenant war was different so enjoy and write to me on how u feel about it.
February 11, 2525: The UNSC makes contact with an alien race called the covenant on the planet harvest. First contact does not go well and begins the start of the human-covenant war.
March 1, 2530: The sangheili discovered the truth about humanity being connected to the forerunners, something that prophets truth, regret, and mercy tried to keep hidden from the other races of the covenant. The arbiter of that time Ripa 'moramee executed the prophets, and went to a human controlled world to ask for forgiveness to the crimes they committed.
March 2, 2530: The UNSC colony groombridge-1830 located 29.7 light years from sol is visited by a covenant corvette, at first the colony thought they were under attack instead the corvette sent a signal to the planet requesting a ceasefire between the covenant and humanity. The UNSC sends Admiral Preston Cole and a fleet of a hundred ships to confirm the covenant request for a ceasefire.
March 3, 2530: The human-covenant war is over a treaty was signed to signify peace, the sangheili offer to help in repairing the human colonies they themselves glassed. The sangheili also offers humanity a place in the covenant, the UNSC agrees in exchange to access to covenant technology.
April 5, 2531: After a year of being with the covenant the UNSC wanted to change the covenant caste system of how they treat other species, the sangheili were hesitant to change but considered it. Eventually it was decided to give the species an embassy on high charity instead of enslaving them, and the covenant would be known as the Orion System Alliance and at the head of the OSA a council was created, the council was composed of a human, sangheili, and a san 'shyuum. The reason for why the san'shyuum have a council seat was there extensive knowledge of forerunner technology, and were the original founding members of the covenant.
June 7, 2531: The reconstruction of the covenant into the OSA was somewhat of a challenges to all members for some others like the sangheili were not, the sangheili still maintain the responsibility of military leadership but shared it with the humans and instead of forcing the other species to fight they may choose to join the OSA military. The san 'shyuum continued to be the scientist of the new OSA and study forerunner technology, but shares this responsibility with the humans, since they no longer lead the covenant or control political affairs, much to their annoyance they must share their power with the humans and sangheili. The other species like the jiralhanae continued to be a part of the military, the sangheili did not like it since both races bitterly disliked each other. The Unggoy was once considered the lowest caste in the covenant but since the humans helped change the covenant into the Orion Systems Alliance the Unggoy were no longer enslaved instead given a choice to join the military or join the civilian sector, some Unggoy joined the military most join the civilian sector, the Kig-yar and Yanme'e were divided on both military and civilian, the Mgalekgolo joined the military and Huragoks were decide to put in engineering for all military ships including UNSC.
August 15, 2534: The reconstruction of the covenant is finally over and the new Orion Systems Alliance has been initiated as the center for galactic government in the Orion arm of the galaxy. The OSA's base of operations is the former covenant holy city high charity now the capital of the OSA, in it resides the OSA council composed of human, sangheili, and san 'shyuum they are responsibly to maintain peace and order with the other species of the OSA.
May 3, 2535: Since the reconstruction of the covenant into the OSA became a success, the UNSC learned much from their new allies and one thing that got their interest was the forerunners. Unknown to many in the UNSC ONI discovered alien technology on some colonies the UNSC established they just didn't know who built it until now, so it was decided to create section four of ONI, there responsibility was to search and study forerunner technologies and to learn the one important question that many in the OSA and UNSC had on their minds Humanities connection to the forerunners, since humans are the only race capable of activating forerunner technologies.
October 21, 2535: On the planet harvest section four discovered what they believe was a forerunner outpost, they sent in a science team to study it. The head scientist Professor Ellen Anders discovered a holographic map of the galaxy which lead them to another forerunner outpost on the UNSC colony Arcadia. The UNSC spirit of fire under the command of captain James cutter was assigned to help section four in search of forerunner artifacts, they went to Arcadia and discovered the outpost. Ellen Anders found coordinates to a planet in an uncharted system unknown to the UNSC and to the OSA species. What they found was an incredible piece of forerunner technology and the worst thing humanity has ever encounter since the human-covenant war.
February 15, 2540: When humanity along with sangheili created the OSA they took on many responsibilities one being in part with help enforcing and maintain order in the galaxy. In order to keep up with sangheili warriors the UNSC decided to create more Spartan-II's. The ones that still survived the insurrection wars and the human-covenant war was part of the special operations division or known as Specops, Specops was created by the OSA council as agents to help maintain order in OSA space. Specops has the authority to do whatever is necessary to get the job done, any species can join Specops but few do cause of the high mortality rate in training on the planet Sathur an OSA controlled world for Specops. In the UNSC it was decided that only Spartans can join Specops because of the extreme training and high mortality rate Specops goes through.
November 5, 2542: Office of Naval Intelligence puts forward a plan to help create a new counter-espionage and intelligence gathering for the OSA with the help of the Sangheili Ossoona division that was responsible for helping the covenant spy and intelligence gathering, they create a new organization that provides spying, counter-espionage, information gathering for the OSA military and Specops and it will be called the Union.
August 30, 2552: A UNSC patrol fleet under the command of Admiral Jacob Keyes was assigned to watch for pirate activity instead he discovered an object in space of forerunner design a ring the size of a planet. Admiral Keyes took images and sent them to UNSC High command. High comm received the images and looked through the information they obtain about the Forerunners. What they found was the ring is called halo and it was an important part of the former covenant religion, the UNSC sent the information to the OSA about halo. When the OSA council learned the discovery of halo the human and sangheili thought it would be best to hide this info from the rest of the OSA but the San 'Shyuum Councilor was an overzealous religious person still continuing the old covenant religion wanted to tell their true believers about it, ultimately it was kept quite.
September 2, 2552: Science teams from the OSA were sent to halo to study it and to find out it's purpose what they got was a lot more than a new piece forerunner tech. On halo a team accidentally open a chamber that released a parasitic life form that consumed the science team, the military contingent on halo sent out the message to an OSA group of ships that was assigned by the council to protect the ring, about the parasite a video link to both a UNSC ship and a sangheili battle cruiser saw images of the parasite consuming both species it was decided by both Admiral Keyes and supreme commander Thel 'Vadamee to sterilize this plague in combination with nuclear missiles and plasma weapons they took aim at the first and surrounding area of the infection.
September 4, 2552: Once it was confirmed safe that the parasite was gone they would begin sending in the science team. Section four sent in their own team lead by the great Dr Catherine Hasley. On halo the team found what they believed to be the control room for halo once they were settled they were approached by a forerunner AI calling itself 343 guilty spark through the AI they learned much about the forerunners, the parasite now know as the flood and about halo being a weapon of mass destruction on the galactic scale. It was decided by the OSA council to keep quiet about this information as it would cause a mass panic and hysteria amongst their people and the species.
September 6, 2552: Through further studying halo and continue talking to the monitor of installation four the OSA learn there are seven halos total in the galaxy scattered somewhere. The monitor 343 guilty spark was unable to divulge the location of the remaining six halos but told the scientists of how we could by finding the ark through a portal that was on earth.
September 7, 2552: The UNSC was very surprised by this information an important forerunner technology was under their noses the whole time, using the reversed engineered luminary used by the covenant to locate forerunner tech, they found some readings between the city of Mombasa and the town of Voi deep underground it will acquire months of digging and excavation to uncover it.
December 27, 2552: After three months of digging they uncover the artifact once uncovered and activated the device created a Slipspace portal to what the scientist believe will lead them to the ark. The UNSC creates an expedition through the portal a fleet of ships composed of scientist and military personal. The commanding officer who is in charge of the fleet was decided to be captain Miranda Keyes, Catherine Hasley was in charge of the scientist division and military contingent was lead by colonel Avery Junior Johnson.
December 28, 2552: The expedition fleet came out of Slipspace over what they believed to be the ark a massive space station bigger then High Charity, many described the ark as a massive wheel with a series of eight curved arms, similar to an octopus or sea star and bearing similarities to a sun. They begin launching drop ships pelican to what they believe to be the control room for the entire facility. A month goes by and from studying the Ark the scientist learn the location of the other halo's and a lot of forerunner knowledge.
January 25, 2553: The UNSC has decided to bring scientist and military personal from all species in the OSA to the ark on UNSC phoenix-class colony ships as the location to earth remains a secret to this day. On the ark the species set up on different arms of the ark, the scientists from each race begins studying and researching the ark. The sangheili with the help from the UNSC begins building a ship yard to build and maintain ships from each species.
February 17, 2553: A Specops fleet is charged with locating and assessing all the halo's condition's finds installation five and destroys it once it was confirmed of a massive flood outbreak.
July 12, 2575: The OSA council has decided to joint colonize worlds in order to bridge the gap between the many species in the OSA, a new way for everyone to cooperate and understand one another.
November 16 2575: The first OSA colony sanctuary is fully developed with the help and full funding of the council which would have taken years from one species to create is ready. Sanctuaries capital city pandorum's architect and buildings are a mixture of human skyscrapers along with the human orbital elevator is setup on the planet, the curve organic and sophisticated style the sangheili and the other races have gotten use too is built on the planet for their own people. The colony becomes filled with the many species in the OSA, for a time the people get along and used to living with one another the only trouble that happens is jiralhanae berserker rage with their own kind but nothing the colonies security force can't handle. The colony is protected by a UNSC ODP and a fleet along with sangheili ships and planetary plasma cannons.
Present day 2657: Humanity and the UNSC is entering a new age, since humanity survived the human-covenant war, the creation of the Orion Systems Alliance, the studying and reverse engineering of advance technology the outbreak of the flood on halo, the search for the ark has made the UNSC strong and prepared for anything, even the biggest discovery yet. A science team has discovered a device of unknown origins near the UNSC colony Shanxi.
This sets up the stage for the confrontation between the OSA council against the citadel council. I hope you have enjoyed this story and feel free to write any feedback on what I should change or make changes too. I will be creating a codex to sort out the small stuff in the next chapter.