Disclaimer: I do not own Mass Effect or it's inherent themes. Anything in this story is of my own making without the goal of financial gain.

AN: Hello there and welcome. My name is UNSC Historian. First off, in this story I am going to try my best and mix both the Mass-Effect and Halo universes. Now I know many people will prefer their own version of such a crossover but as the reader could you please try and see it from my point of view for a second? That is if you actually end up having a problem with my story anyway.

What I'm trying to do is mix both universes with their respective strengths and themes. Note I said Try and not masterfully weave them into a glorious whole. Now in this, Humanity will stick to it's inherent ingenuity as provided by the Halo universe but will incorporate useful technologies that the Mass Effect universe uses. The Covenant will not however as they use more advanced, reverse engineered Forerunner technology. That isn't to say that certain client races won't use them.

This chapter is a time-line event and will hopefully provide you with an adequate idea of how everything is before we get into the first chapter.

So here goes and I hope you enjoy it.

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Trials and Tribulations

History of the Galaxy

110,000 B.C – The Ancient Human Empire is defeated at the hands of the Forerunner Ecumene. The Human Empire destroys all evidence of it's research developments, among them is the cure to the Flood infection, which they have been fighting for years to save the galaxy from destruction.

The Forerunner's viewed Humanities expansion as problematic and a violation of the Mantle. Therefore they beset upon the task of de-evolving their society to stone age status to restart.

100,000 B.C – The Forerunner's activate the Halo Array, eradicating all sentient life with sufficient biomass to sustain the all consuming parasite known as the Flood. It was the last resort after attempting thousands of other plans. In a brief moment of glorious conflagration, the parasite was extinguished and the Forerunner's Sentinels set to work bringing life back to it's original home.

50,000 B.C – The Prothean Empire is harvested by the Reapers alongside all advanced life. The Reapers leave certain facilities intact so that the next civilizations can progress faster. They retreat through the Citadel Relay and await the next cycle.

2100 B.C – The San'Shyuum civil war ends with the Reformists entering the Forerunner Dreadnought and leaving their home planet and system.

938 B.C – The San'Shyuum encounter the Sangheili whilst searching for Forerunner artifacts in the Sangheili home system. As both have different ideologies on how to handle Forerunner artifacts, this encounter quickly descends into open war.

876 B.C – After decades of conflict, the Sangheili violate their own religious beliefs in order to defeat the San'Shyuum. With there being no point in continued warfare now that they both hold the same beliefs, they form an alliance known as the Covenant. The Writ of Union is made and they cease their conflict. They begin to journey into the stars together on a religious journey.

784 B.C – During one of the first ages of Conversion, the Covenant encounter the Lekgolo on their home world Te. The Covenant forcefully absorb the Lekgolo as a client race after a brief but brutal conflict against them.

Around this time the Covenant discover their first Prothean ruins. It is quickly believed they have already set upon the Great Journey. They discover the Mass Relay network and utilize it.

648 B.C – The San'Shyuum home world is reported to have been destroyed in a supernova. The construction of High Charity begins to provide a capital and new home for the Prophets.

580 B.C – After developing FTL capabilities based upon Prothean designs, the Asari discover the Citadel at the heart of the Mass-Relay network.

520 B.C – The Salarians reach the Citadel after proceeding along similar lines of the Asari. They open diplomatic relations with one another.

500-200 B.C – The Citadel Council is formed.

First contact between the Volus and the Citadel Council occurs, the Volus are commissioned to create the Unified Banking Act which links all galactic economies and establishes the credit as the only currency to be used.

The Turian Unification wars occur during this period. The Turian Hierarchy becomes the representative of the Turian species.

The Battle of Thermopylae occurs. 300 Greek Spartans hold a narrow passage against thousands of Persian forces. Buying Greek time to gather it's armies and repel the invaders, at the cost of each Spartans life.

200-1 B.C – The Citadel Council grants the Volus the honour of being the first non-council race to hold an embassy on the Citadel.

First Contact is made with the Batarians, they are granted an Embassy a century later.

The Asari encounter the Elcor and integrate them into galactic society. Within one Elcor life time they are granted an Embassy.

First contact is made with the Hanar and Quarian races.

1-300 A.D – Salarian explorers encounter the Rachni, they prove to be hostile and begin to wage war against the galaxy.

The Rachni wars rage on, the Citadel Races losing dramatically in the conflict until the discovery of the Krogan. The Krogan are uplifted to serve as soldiers beside the Citadel races and the tide turns.

The Turian Hierarchy enter the galactic stage with their formidable military and fleet size. They are requested to aid in the conflict against the Rachni. They agree and the Rachni begin to lose ground rapidly.

Tensions between the Turian and Krogan soldiers deteriorate. War breaks out between them as the Krogan assault a Turian colony. War rages on all fronts and threatens to destabilize the entire galaxy.

Covenant vessels enter Citadel Space and begin to do as their mantra dictates. They start to absorb them into the Covenant with force if necessary. All attention is pivoted to the Covenant, even the Rachni cease assaults on Citadel worlds and turn to face the new threat.

One by one, the Covenant defeats the Citadel races and the Rachni. The first to fall is the Rachni, then the Batarians, Quarians, Hanar, Volus until eventually the Citadel Council realises it cannot continue the war and they surrender.

The Turians continue to resist alongside the Krogan but are nevertheless beaten when the Covenant glass parts of Palaven and Tuchanka. The Citadel Council is dissolved and absorbed into the Covenant Empire. The Covenant finds use for each and every race that they have quickly dominated, each race finding it's own niche to settle into. Citadel space is now absorbed into Covenant space and the Citadel is used as a secondary home to the San'Shyuum.

The Covenant assimilates each culture and inserts it's own dogma. The next generation will grow into faithful and loyal followers of the Covenant.

700 A.D – After centuries of rapid expansion, the Krogan begin to rebel as they overflow their worlds with it's populations. Without ships under their own control to ferry them elsewhere, they begin to fight amongst themselves for resources, land and food.

The Covenant send fleets to bring the Krogan population in check. Glassing several planets and reducing the Krogan population significantly. The Sangheili ship masters vowed to keep the Krogan population in check if the Krogan cannot do it themselves.

In response to the glassing of Krogan worlds, Krogan revolt on many other planets starting the Krogan rebellions. Seizing Covenant vessels, they begin to fight the Covenant. Salarian science teams, under orders from the San'Shyuum, create the Genophage to remove the high Krogan birth rate. The Krogan population quickly declines and is dragged back under Covenant control. The Krogan serve as a reminder of what happens to Heretics and traitors.

900 A.D – For their skill and prowess in battle, the Turians are recognised and granted similar status to the Sangheili, though they are their subordinates. Even though they have a small section on the High Council, they are still a minority. Turians have already integrated into Covenant society the easiest due to their community first view point. It is from this example that other races aspire to get voices on the High Council.

The San'Shyuum begin to consider sharing their religious roles with the Hanar. The Hanar believing in the Great Journey almost as feverishly as the San'Shyuum. Eventually it is accepted, but the Hanar can never attain High Prophet status, they will serve as the Prophet's subordinates willingly.

1112 A.D – The Covenant discover the Yanme'e. An insect race like the Rachni. They are absorbed into the Covenant as a slave race alongside the Rachni.

1342 A.D – The Covenant discover the Kig-Yar. Though the Kig-Yar attempt to resist absorbtion into the Covenant, they submit as they understand that they are a vastly superior force. They become traders and explorers (also pirates and smugglers alongside the Batarians who are also slavers).

1400 A.D – The Covenant encounter the Drell on their dying home world. They are saved by Covenant vessels after being absorbed into the Covenant. They begin to serve as personal guardians of Prophets and Hanar (The two most religious species in the Covenant.).

1789 A.D – After gaining much influence, the Asari are granted a position on the High Council. Their efforts at training the biotic individuals of the Covenant population is widely recognized as their achievement, among other desirable traits.

The first sightings of the Collector's occur around this time. They are widely dismissed as rumours due to the relay manipulation they apparently perform.

1892 A.D – The Salarians are granted a position on the High Council. This is in due part to their excellent intelligence gathering capabilities and their overall swiftness in scientific matters. Even though they received stiff opposition from the Sangheili and Turians, they were welcomed openly by the rest of the High Council.

1921 A.D – The Geth are constructed by the Quarians. They are under scrutiny by the Covenant due to the Holy texts speaking of machine rebellion. After careful guidance and counter-measures are developed, the Geth are absorbed unofficially to provide labour and war machines.

1945 A.D – The UN is established on Earth in the wake of WWII.

2070 A.D – The first VI systems in Human history are created and begin use in all manners of society.

2090 A.D – The first AI system is created by Humanity by accident but nonetheless becomes common place in Human society due to their usefulness. Wide-scale colonization of the Sol system begins by the Human species.

2130 A.D – Medi-Gel is created by the Sirta Foundation, a medical mega-corporation based on Earth.

2142 A.D – The Covenant discover the Unggoy species on their home world Bahalo. They surrender almost immediately in the imposing and intimidating presence of so many different alien races. The Unggoy are enslaved to much joy of the Batarians.

2160-2170 A.D – After years of political unrest and ideological differences, the entirety of Human controlled territory in the Sol system descends into a civil war between the Friedens, Koslovics and UN forces. The Interplanetary Wars, as it is known later, ends with the newly formed UNSC victory over the Insurrectionist forces. The UEG is formed during this time to provide a single government for the Human species with the UNSC providing a single military to protect it.

2291 A.D – A group of researchers headed by Tobias Shaw and Wallace Fujikawa, also funded by the UNSC, secretly develop the Shaw-Fujikawa Slipspace Drive. It is a practical means of travelling faster-than-light. This new engine allows vessels to tunnel into the slipstream (also called slipspace). Slipspace is a domain with alternate physical laws, allowing FTL travel without the relativistic side effects. Short jumps can take up to 2 months while long jumps can take up to 6 months, the science division develops a resonance field generator which allows for drastically shorter transit times between stars. No scientist is sure why but an odd flexibility to temporal flow is present in the slipstream. There is usually a 5 to 10 percent variation in transit times.

2310 A.D – The UEG unveils a line of colony ships intended to alleviate the growing over-population crisis on Earth. With the state of the Earth's population, it becomes a widely welcome idea. They also announce that they will be sending Military detachments with the colony ships to help alleviate fears, as the technology is still new and expensive.

Shortly after this is the birth of the Inner Colonies of Human territory.

The Committee of Minds for Security (A collection of AI's which meet in secret to help guide their makers path) holds a session, discussing the likelihood of contact with intelligent extraterrestrial life. They decide to base the models of such an event with intelligent and hostile extraterrestrials who are more advanced than their makers because if they were not, they would pose no threat.

2310-2400 A.D – Human territory has expanded into 400 systems with Earth at the centre. The inflow of resources to Earth helps fund more colony ships and it's military defence capability. This is an age of Human expansion and great wealth. These systems would become the Inner Colonies, the political centre of the Human race.

During this time there are many Unggoy rebellions until they are eventually granted more freedoms such as joining the military, but they are still a slave race. Bahalo is partially glassed during this period.

A series of Arms Manufacturers and Defence Contractors for the UNSC form together into Misriah Armouries. They become the sole provider for the UNSC military.

In this period in a region on Mars, a mining corporation uncovers a hidden facility after picking up on it's signal, which was on all frequencies. After uncovering the structure they realised it's implications and alerted the UNSC. It wasn't long before the news quickly spread into the public's view and the realization that followed.

Shortly after gaining access to the facility and it's data core, the UNSC science teams discovered that the aliens were known as Protheans. They deduced that the ruins had last been manned roughly 50,000 years ago and had not been entered since. After exploring the facility and examining the docked craft in the hangar, they also quickly realised that they utilized a type of technology which would end up bolstering Humanities own. From this discovery, Mass Effect technology soon begun it's usage in Human society. All thanks to the newly recognized Element Zero.

The data from the Prothean ruins mentioned another form of FTL which the Protheans utilized, from a Mass Relay. These Mass-Relays help travel times enter a much faster pace around the galaxy and the local relay is encased in ice and mistaken for a moon around the planet Pluto.

The Committee of Minds for Security ran an uncountable amount of different scenarios on this new discovery. They all came to one conclusion, that the Relay opened a gaping hole into the centre of Human territory. If the Protheans are still alive and are hostile, which the Committee assumed, then it would destroy the Human race. They subtly suggested to their Human masters into thinking it was their own idea, that they should dismantle the Mass-Relay and determine what can be learned from it and whether or not it can be safely used for Human use.

Science teams began to scour Human space for sources of element zero for use in Human society. After a few years they began to find plenty of systems which housed significant sources of element zero. Shortly thereafter, the first prototype technology is created with Eezo in every aspect from civilian appliances to military applications. The new wonder element didn't disappoint.

Misriah Armouries developed the first Eezo integrated weapon system which could fire without the need for ammunition cartridges, removing a logistical problem for the military overnight as it proved to deal more damage than conventional weapons.

2410 -2430 A.D – After 30 years of dismantling the Charon Relay and studying it, the science teams discovered it's systems respond to an IFF signal, presumably a Prothean signal, to provide better transit. The scientists, technicians and engineers modified it to always require an IFF of Human coding and installed a "Dumb" AI. The AI would request mass specifications after confirming the ships origin and IFF. This created a way for the Mass-Relays to be used without causing harm to Humanity, or putting them at significant risk.

The UNSC proceeded to send teams to the other relays which have been discovered throughout Human space and do the same, creating a relay network which responds only with Human permission, either by the UEG or the UNSC. Human territory continues to expand exponentially as more relays are discovered in the Orion Arm of the galaxy in which Humanities fledging empire resides.

Tests with mass effect technology in slip-space proved to be problematic. It could only be utilised to a certain extent before slip-space sheared the vessel in half due to slip-space having a certain mass requirement for usage. Nevertheless, travel times within slip-space shortened dramatically, short trips being as long as a month and long trips as long as 2 months.

Scientists also discover Prothean ship classifications and diagrams. What confuses them is that Protheans couldn't build ships over 1.5 km due to the extensive mass effect requirements. But yet Humanity had developed colony vessels over 2 km long before the discovery of element zero. It is quickly assumed that Protheans must have developed on an element zero rich world to have such a limited imagination. Human engineers and ship-builders being able to take it in stride that they succeed where an ancient advanced civilization had failed.

2430-2525 A.D – In this period, Human space expands to control 947 systems and no other sign of intelligent alien life anywhere other than Mars. Other than Earth which has become the political centre of Humanity, Reach has become the Military forefront alongside scientific endeavours. The outermost colony from Earth is Shanxi, followed closely by Harvest.

Biotic individuals throughout Human society become recognized and are gathered to provide a study of them. It is believed they gained these abilities from exposure to element zero prior to birth. They are implanted with consent to help give them better control over their abilities.

In the outermost colonies, political strife is commonplace. Old political movements come into power such as the Neo-Friedens and Neo-Koslovics. They slowly gain favour amongst some of the outermost colonies and begin their dissension from UEG control.

In 2492, the Jiralhanae are discovered by the Covenant and are quickly conquered. The Jiralhanae quickly adapt and integrate into the Covenant and fully accept the Covenant religion.

In 2498, the Insurrection reached boiling point and erupted into open warfare between the UNSC and the individual factions trying to gain independence. The conflict raged from one of the outermost colonies such as Mindoir, location of the Mindoir Massacres, to one of the inner colonies Elysium in which the rebels attempted an offensive and were swiftly routed and pushed back to their moon base of Torfan.

The UNSC gave no quarter and opened fire on Torfans surface with MAC rounds from orbit. The resulting devastation caused the moons crust to erupt into grotesque forms. A famous location being the Hell-mouth which seeps deep into the core of the moon.

Following up on the attack on Torfan, the UNSC attacks Akuze. The battle that took place disturbed a creature which slaughtered both sides indiscriminately. This would be the first encounter of a Thresher Maw. Though the battle was won by the UNSC after killing the Thresher Maw, they retreated nevertheless when more rose to the surface and begun to attack entire encampments.

The Spartan-II project was initiated, headed by Doctor Catherine Halsey. It culminated with training children from the age of 7-9 into adult super soldiers. Originally numbering at 150, after augmentation only 70 survived the procedure. These soldiers became a symbol of UNSC strength.

The culmination of the Insurrection is when Spartan teams were sent to capture/kill Colonel Robert Watts. Upon completion, the Rebels were left leaderless and crippled. The rebellion quickly dissolved early in the year 2525. Giving enough time for Humanity to rebuild and regroup for the next test of their civilization.

2525 A.D – The colony of Shanxi goes dark. Fearing a rebellion, the UNSC send the scout ship Argo to investigate. Contact with the Argo is lost, further worrying the UNSC and UEG. Battle-Group Alpha is assembled and sent to Shanxi, to discover what is going on.

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Codex Entry: Covenant Empire

Encountered by Humanity in the year 2525, the Covenant Empire has existed for an unknown amount of time and over the years has incorporated, enslaved or out right destroyed any other alien civilization it has encountered. It is a theocratic society with a hierarchic system. It is unknown how large it's territory is, but they are in fact made up of at least 20 alien races that have been encountered and documented.

They use advanced slipspace drives which out perform anything Humanity has created and utilize weaponry which are more advanced than Humanities own, except of course for their mass accelerator weapons. They barely utilize element zero in their Military, it is unknown if they use it in their society.

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AN: So there is your time-line event. I hope it is satisfactory to give you a good idea of how this story is set. Let me know what you think in the review.

UNSC Historian.