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Halopedia Timeline

Primordial Era

• Over 500,000,000 BCE, the Precursors are stated by the Gravemind to have created the Domain, coalescing the sum of their knowledge—encompassing a hundred billion years—into a unified reservoir integrated into their many neural physics artifacts in the Milky Way galaxy. However, the Domain may have been first created long before this, as Forthencho, acting as a messenger for the Gravemind, later stated that it had existed for many billions of years.

Forerunner era

• Circa 15,000,000 BCE, the Precursors create and seed the species that would come to be known as Forerunners on the planet Ghibalb.

• Circa 10,000,000 BCE, the Precursors choose early humans to be the next species to carry the Mantle. Desiring to seize the Mantle for themselves, the early Forerunners rebel against the Precursors and wipe them out almost entirely. After the Forerunners hunt down all of the Precursors in the Milky Way galaxy, the remains of the race retreat into the Large Magellanic Cloud; the Forerunners' Warrior fleets pursue them via probability mirror-reconciled slipspace portals and proceed to finish their work. A number of Forerunners who conscientiously object to the complete destruction of the Precursors are exiled on a barren planet within the Tarantula Nebula; these Forerunners later remain as the only surviving population of the expedition to the Large Magellanic Cloud.

• In the face of extinction, most of the Precursors reduce themselves to inert powder, intending to regenerate their forms later. However, this dust would deteriorate over the coming eons, eventually bringing forth the parasitic Flood. However, one intact specimen remains in deep stasis and is buried within a remote asteroid a million years afterward.

• Circa 9,000,000 BCE, the Primordial, a dormant Precursor, is said to have arrived on the edges of the galaxy. This being is later discovered by early spacefaring humans during the last decades of the Human-Forerunner War and brought to Charum Hakkor in a stasis capsule.

• Prior to 1,100,000 BCE, ancient humanity achieved its earliest known spacefaring technological state and settled on numerous worlds along the galactic margin. They would later experience several dark ages resulting in the loss of most of their historical records and knowledge before eventually encountering the Forerunners.
• Around 1,100,000 BCE, the Forerunner Theoretical known as Boundless begins to study a particular star within the Path Kethona galaxy. When she continues her work in defiance of Warrior orders to the contrary, she is eventually prosecuted, her studies are suppressed, and she is forced to enter a Cryptum.
• A thousand years later, Boundless' Cryptum is opened and it is discovered that she has died inside due to a malfunction in the Cryptum, supposedly resulting from sabotage. Her former students discreetly dispose of her body.

• After Boundless' death, the entire Theoretical rate is absorbed into the Builders.

• Circa 150,000 BCE, the Forerunners are claimed by some records to have risen as the preeminent species in the Milky Way Galaxy by advancing technological discoveries gathered from the remnants left by prior ancient races. Believing themselves responsible for the lives of all those less advanced then they, the Forerunners initiate the Mantle.
• Humanity is believed by the Forerunners to have "moved their interstellar civilization outward along the galactic arm" around this time, possibly to escape Forerunner control.

• The capital, the center of the Forerunner ecumene, is constructed around this time.

• Faber-of-Will-and-Might, a future Master Builder, is born this year.

• Shadow-of-Sundered-Star, later known as the Ur-Didact, is born this year.

• Circa 107,445 BCE, human colonists proceed to uncover crashed vessels containing fine organic powder on both inhabited and deserted worlds near the edges of the Milky Way Galaxy. This powder is administered to the domesticated Pheru, which begin to exhibit more docile behavior; unbeknownst to humanity and their San'Shyuum allies, the powder begins to alter the Pheru's genetic makeup. Centuries later, the Pheru begin to show outward signs of mutation and cannibalize one another. Soon, both humans and San'Shyuum who are exposed to the powder begin to exhibit the same symptoms.

• The Flood then begins to take over hundreds of worlds, turning its victims into misshapen forms. Humanity begins all-out war against the Flood. During their war against the Flood, humanity desperately invades a minor sector of Forerunner space, sparking the human-Forerunner wars.

• Circa 106,538 BCE, human colonists arriving at a ravaged planet on the edge of the Milky Way Galaxy discover an exceedingly ancient stasis capsule. This capsule is the prison of the ancient being known as the Primordial, supposedly the last intact Precursor. Yprin Yprikushma transports the capsule and its prisoner to Charum Hakkor for further study.

• Yprikushma's science teams revive the Primordial and place it in a timelock held in a vast arena on Charum Hakkor, soon after devising a way to communicate with the creature. The answers given by the Primordial to the humans' questions about the Flood are so traumatizing they are believed by Forthencho to have demoralized humanity to the point of contributing to their defeat against the Forerunners later on.

• Yprin Yprikushma begins to push humanity to conduct more intensive research into Forerunner technologies recovered during earlier human-Forerunner conflicts. Through the technological advances gained, she buys humanity several more decades in its war with the Forerunners.

• Some time afterward, the Flood begins to recede from the galaxy; while this is thought to be due to a cure created by humanity, no cure ever actually existed; the Flood's withdrawal is instead due to the Gravemind's long-term strategy. With the Flood seemingly dying out, all traces of the parasite's existence are eventually removed from the Milky Way by humans, their San'Shyuum allies, and Forerunner Warrior-Servants. Throughout the war, most Forerunners remain unaware of the Flood's existence, believing stories of the parasite to be an excuse for humanity's aggressive expansion. The Flood will not seen again for nine millennia.

• Circa 106,498 BCE, the final conflict in the human-Forerunner wars begins. The Forerunner Warrior-Servants, led by the Didact, push humanity back to the Charum Hakkor system, the core of their interstellar empire, which is then effectively cut off from available reinforcements of both humans and their San'Shyuum allies. For the next fifty years, humanity holds off attacks by the Forerunner fleets, until their defenses eventually fail after three final years of repelling assaults on the system in a constant stream.

• Circa 106,445 BCE, the final battles of the human-Forerunner wars are fought, concluding in the humans' standoff at Charum Hakkor. Stretched thin due to fighting two wars simultaneously, humanity loses the war and the Forerunners eliminate all traces of humanity's former interstellar civilization. The Librarian moves the surviving humans to their homeworld, Erde-Tyrene, and establishes a research station there. With their civilization and technology dismantled, humanity regresses to tribal hunter-gatherers for nearly nine thousand years, eventually developing primitive civilization.

• Circa 98,445 BCE (approximately a thousand years prior to the firing of the Halo Array), the Forerunner Prometheans, opposed to the construction of the Halo rings, lose their political battle against an extreme faction of the Builders led by the Master Builder, Faber, and are forced out of the Council. Many are disgraced or executed while others choose the alternative of exile in a Cryptum. For the next thousand years, the Council continues to marginalize and diminish the role of the entire Warrior-Servant rate.

• The Didact enters his first, thousand-year exile in a Cryptum on Nomdagro. The Cryptum is later secretly moved to Erde-Tyrene by the Librarian.

• The Deep Reverence is retired near Janjur Qom, under the care of the Confirmer.

• With the final obstacle to his plan removed, Faber commissions the construction of the original twelve Halo rings from the guild of Bornstellar's father.

• Growth-Through-Trial-of-Change decides to become a Lifeworker instead of a Builder. She is rejected by her family as a result, and is adopted by a foster family.

• Circa 98,395 BCE, the Librarian undertakes on a mission to study the origins of the Flood in the satellite galaxy of Path Kethona. In Path Kethona, the Librarian and the crew of her explorer vessel, Audacity, discover a world with a population of primitive Forerunners. On this planet, she learns the truth about the Precursors' disappearance ten million years earlier: the Forerunners rose up against their creators and annihilated them in defiance of the Precursors' choice to pass the Mantle on to humanity. The Librarian would keep this information to herself at the time, fearing that the Builders in control of the Old Council could potentially use it against her or the Didact.

• Circa 97,745 BCE, first contact is made between the Forerunner Primary Pioneer Group and the Flood on G617 g1. A military team is sent in later but is subsequently lost. The Flood escapes the planet, thus beginning the three-century-long Forerunner-Flood war.

• The Boltshot comes into use with the Forerunner military near the beginning of the century.
• Riser is born in the city of Marontik on Erde-Tyrene around this time.

• In approximately 97,495 BCE or slightly earlier, the Forerunner Ecumene Council assigns the Contender-class ancilla Mendicant Bias to test Installation 07 near Charum Hakkor. The installation, fired on a system-wide power setting, destroys all neurologically complex life and Precursor structures in the system and accidentally liberates an ancient Gravemind known as the Primordial, which is transported on the ring on Master Builder Faber's orders. Soon after, Faber tasks Mendicant Bias with interrogating the Primordial and Installation 07 is transported in an unknown location. Over the course of their 43-year conversation, the Primordial manages to turn Mendicant Bias against its makers and causing it to join the Flood's cause to destroy the Forerunners.

• At the same time the Librarian returns to Earth to index the human species. Sample members of the species are removed from the planet and held on the Ark.

• In 97,445 BCE the Forerunner-Flood war came to a close with the activation of the Halo Array. It should be noted that all of the events listed here are approximate at best, occurring over the course of several years during the last decade before the firing of the Halo rings in the year 97,445 BCE. As no definite chronology has been established for that timeframe, the events therein are recorded on this page for the sake of convenience.

• Roughly ten years before the Flood conflict's conclusion, the father of Maker-of-Moons, a high-ranked Builder, is assassinated by Master Builder Faber's Builder Security minions.

• The Librarian visits the primary San'Shyuum quarantine world Janjur Qom to collect specimens of the San'Shyuum as part of the Conservation Measure, sparking unrest among the San'Shyuum population. After Master Builder Faber arrives some time afterward to question the San'Shyuum elders about the Flood, the San' Shyuum rebel against his forces.

• The Didact is resuscitated from his exile in a Cryptum by Bornstellar Makes Eternal Lasting, Chakas and Riser. They later make their way to Janjur Qom, where they are captured by Master Builder Faber. The Didact is interrogated and left to die in a Flood-infested system, while an offshoot of his consciousness lives on in Bornstellar's body through an imprint acquired in his mutation.

• Shortly afterward, the Master Builder orders the Contender-class ancilla Mendicant Bias to use Installation 07 to put down the San'Shyuum rebellion by sterilizing the entire system.

• As a result of the Master Builder's activation of the Halo ring, many Lifeworkers and Warrior-Servants on Installation 07 rebel against his forces, but are mostly defeated.

• A crisis occurs in the Ecumene Council due to the Master Builder's unauthorized activation of Installation 07; many councilors resign in protest while younger ones take their place. Faber is arrested and placed on trial in the Forerunner Capital. Eleven of the Halos are brought to the Capital, awaiting a decision to have them decommissioned. Installation 07 and Mendicant Bias remain missing.

• During Faber's tribunal, Mendicant Bias, convinced to turn against its masters by the Primordial, brings Installation 07 to the Capital system and launches an assault on the Forerunner government. While the Council's fleets respond to the attack and several of the Halos are destroyed, Mendicant successfully fires Installation 07 before the Halo is forced to retreat into a system near the galaxy's edges.

• Having survived Mendicant Bias' attack on the capital, Bornstellar, Glory of a Far Dawn and Splendid Dust of Ancient Suns arrive at the greater Ark, where they are healed by the Lifeworkers. As most Forerunners believe the original Didact to be dead, the Didact's consciousness takes control of Bornstellar in order to assume command of Forerunner military forces after a thousand years of exile and continue his mission against the Flood; subsequently, Bornstellar adopts the title IsoDidact.

• Shortly afterward, the IsoDidact and his fleet track down Installation 07. Although the Halo takes heavy damage, it survives and is transported to the greater Ark. Afterwards, the installation is sent to its final location, to be later joined by the six rings of the newer Halo Array.
  • The Primordial is imprisoned once again, and is interrogated - and eventually executed - by the IsoDidact.
  • Mendicant Bias is captured, deactivated and disassembled to its disparate components which are then distributed across the ecumene.
  • The mind of a mortally wounded Chakas is used as the template for the monitor later to be known as 343 Guilty Spark.

• The Ecumene Council is reconstituted as the "New Council" and the Didact's plans of a strategy to use shield worlds to combat the Flood are taken into serious consideration again. The use of the Halos is delayed.

• For a period of at least three years following the crisis at the Capital, Master Builder Faber, thought dead by the ecumene at large, carries out his own small-scale campaign to combat the Flood with a crew of Builder Security and disgraced Warrior-Servants in a secluded region of the ecumene. He captures and haphazardly decontaminates small Flood-infested ships and then hands them over to Warrior-Servant crews. Due to inadequate decontamination, many of the ships are overrun by Flood still on board.

• The Juridical rate is given unrestricted access to all citizens of the ecumene by the Council, with the mandate to investigate matters surrounding the attack on the Capital, Forerunner and human origins, as well as the fate of the Precursors. To this end, the Juridicals dispatch Catalog to collect testimony from key Forerunner figures, including the Librarian, Ur-Didact, IsoDidact and Faber.

• The Ur-Didact, having been left to die in a Flood-infested system by the Master Builder, encounters active Precursor star roads near Uthera Midgeerrd. The Didact is subsequently captured and tortured by the Gravemind. Afterwards, the Gravemind releases the Didact, who is rescued and taken to the Capital system by the Master Builder.

• The Librarian and the IsoDidact arrive at Earth to oversee its evacuation operation and to give their testimonies to Catalog. However, the Flood's arrival in the sector prompts the IsoDidact to leave to defend the core of the ecumene while the Librarian continues her mission; the two will not reunite until four years later.

• Mendicant Bias is reassembled and reactivated by a Gravemind after the Flood overruns the facilities in which the components of the AI were held.

• Catalog is captured by the Flood and corrupted with the logic plague, subsequently spreading the infection across the Juridical network. With the network suspended, Juridicals are eventually forced to cease all Forerunner legal proceedings indefinitely.

• The Flood begins to reactivate and appropriate formerly dormant Precursor artifacts, allowing them to easily overpower Forerunners in combat. Already weakened and exhausted Forerunner defenses continue to fail at an increasing rate.

• Over a year before the end of the war, following irregular outages for several years, the Domain goes permanently inaccessible to all Forerunners and ancillas due to the Flood's widespread tapping into its underlying neural physics architecture.

• Four years after the evacuation of Erde-Tyrene, the Librarian, the IsoDidact and the Ur-Didact reunite in their family estate on Nomdagro. The planet is subsequently overrun by the Flood.

• After the Capital system is lost to the Flood, command of the ecumene and the bulk of its remaining population is placed at the greater Ark. In the face of imminent defeat, the Master Builder is restored to command and a decision is made to use the Halo Array to purge the galaxy of life and thus starve the Flood. The IsoDidact is tasked with carrying out this plan.

• Mendicant Bias and its fleet of Flood-controlled ships and Precursor constructs assault the greater Ark.

• Anticipating that Omega Halo's human population may be at risk, the Librarian sends Chant-to-Green to collect more humans from Earth to ensure their numbers will be sufficient to repopulate the species.

• While the Forerunners attempt to evacuate the greater Ark, the Ur-Didact uses a Composer to harvest the preserved human specimens on the nearby Omega Halo in order to use their patterns to create AIs for his army of Promethean Knights, a desperate and futile effort to combat the Flood via conventional means.

• Master Builder Faber fires Omega Halo, sterilizing the local galaxy of Path Kethona of sentient life and clearing a temporary path past the star roads laying siege on the greater Ark.

• The greater Ark and Omega Halo are destroyed by star roads; Faber and most high-ranking Forerunner commanders are killed on Omega Halo, while the IsoDidact is saved by Monitor Chakas. Only a fraction of the Lifeworkers' biological specimens survive and are transported to the secret Installation 00 by the few surviving Forerunners.

• The Librarian infiltrates Requiem and imprisons the Didact in a Cryptum.

• The Librarian journeys to Earth, planning to draw the Flood there in order to give the IsoDidact time to fire the Halo rings. She sends Chant-to-Green to the lesser Ark, along with the remaining humans gathered from the planet, and passes her title of Lifeshaper on to Chant.

• At Installation 00, the IsoDidact assigns the monitors for each Halo installation and has the rings distributed across the galaxy.
  • Monitor Chakas is renamed 343 Guilty Spark and assigned as the caretaker of Installation 04.

• The Librarian, stranded on Earth, initiates the burial process of the Portal at Voi. As she spends her last hours in the savanna, the Gravemind sends down imprinted ancient human essences to reveal the Domain's true nature as a Precursor creation; as a result, the Domain will be destroyed when the Halos fire, leading to the loss of not only all Forerunner history but also the knowledge the Precursors had collected over the course of billions of years.

• As the IsoDidact prepares to activate the rings, Mendicant Bias assembles all Flood-controlled vessels into a fleet of 4.8 million ships, and breaches the Maginot Sphere. On the other side awaits Offensive Bias with the remains of the Forerunner fleet. As the two fleets engage each other in an enormous naval battle, the Halo Array is fired. The Halo pulse kills all sentient life within three radii of the galactic center, including any Forerunners not located on the Ark or within Shield Worlds. Minutes after the firing of the Array, Mendicant Bias's fleet is decimated by Offensive Bias.

• The remains of Mendicant Bias are brought to Installation 00. The surviving Forerunners hold a trial to the AI for its betrayal; Mendicant Bias is entombed in the installation afterward.

• Every sentient species indexed in the Ark is returned to their homeworlds as a part of the Conservation Measure, the Homo sapiens species begins migrating out of Africa.

• The few surviving Forerunners go into self-imposed exile.

• May: A report is sent to 2401 Penitent Tangent regarding Flood containment failure in a cold storage facility, urging assistance due to the dangers of a full Flood outbreak. Penitent Tangent ignores this report and protocol despite multiple and more urgent reminders. He continued to ignore this for another 99,779 years, at which point a full outbreak had already occurred, but by then it was too late.

• Circa 57,448 BCE, a meteor bearing a small Forerunner artifact crashes on the planet that will be known as Sigma Octanus IV. It will be discovered by humanity approximately 60,000 years later.

Rise of the Covenant era

• Circa 40,000 BCE, an unidentified alien vessel crash-landed in Sector 1215 of Installation 04. Sometime prior to the crash, the ship started broadcasting a distress signal repeating every 72.83 seconds. After attempting to translate it, 343 Guilty Spark blocked the signal, as no communication revealing the location of any of the Halos was allowed.

• The year 2200 BCE saw a major turning point in the history of the San'Shyuum (Prophets). After centuries of unity the San'Shyuum become divided into two groups, the Stoics who believe that Forerunner relics were sacred and not to be altered, and the Reformists who wish to more closely examine the artifacts and use them for their own purposes. This fundamental disagreement sparks the San'Shyuum Schism.

• In 2100 BCE the century-long San'Shyuum Schism comes to an end as one thousand Reformists enter the Forerunner Dreadnought and flee the San'Shyuum homeworld Janjur Qom.

• In 2100 BCE the century-long San'Shyuum Schism comes to an end as one thousand Reformists enter the Forerunner Dreadnought and flee the San'Shyuum homeworld Janjur Qom.

• After decades of struggle between the Sangheili and San'Shyuum in the Sangheili-San'Shyuum war, the Sangheili finally accept that they must adapt and study their Forerunner relics or face defeat at the hands of the San'Shyuum. The Sangheili warrior priests reluctantly begin using their relics to improve their warships, arms and armor.

• Circa 860 BCE, the Planet of Blue and Red becomes a location of strategic importance in the San'Shyuum-Sangheili War. The San'Shyuum arrive at the planet and descend to its surface in an attempt to claim the world's Forerunner artifacts from the Sangheili. During the Skirmish of the Planet of Blue and Red, High Lord Mken 'Scre'ah'ben witnesses Field Commander Ussa 'Xellus' talent as a military strategist.

• The Sangheili and San'Shyuum end their war, merging to form the Covenant. The Council of Concordance ratifies the Writ of Union, clearly defining the roles of the San'Shyuum and the Sangheili.

• In the first Age of Reconciliation, the Covenant face rebellion by Sangheili heretics opposed to the Writ of Union. Led by their leader Ussa 'Xellus, the heretics known as the Ussans depart from Sanghelios to Shield World 0673 in order to seek sanctuary from the Covenant.

• In the First Age of Reconciliation, the Prophet of Inner Conviction, the Minister of Relative Reconciliation, and the Sangheili treaty commission reconvene to discuss the disappearance of Ussa 'Xellus and his followers.
• The Ministry of Anticipatory Security is established by the High Prophet of Excellent Redolence and R'Noh Custo is appointed as its Minister.
• The newly designated Minister of Anticipatory Security tasks the Prophet of Inner Conviction with a mission to Janjur Qom to retrieve a group of Stoic females and a Forerunner Luminary, threatening to use his new-found influence to place the Prophet on the Roll of Celibates if he declines. Despite his best efforts, the High Prophet of Excellent Redolence forces Inner Conviction to reluctantly accept command of the expedition.
• The Ussans continue to develop their new colony on Shield World 0673, calling it the Refuge. Monitor Enduring Bias informs Ussa and Sooln 'Xellus of the shield world's "Disassembler" process that allows the world to break itself apart and have its disparate parts remain habitable. Intrigued, Ussa investigates the process further.
• The Prophet of Inner Conviction is given command of stealth corvette Vengeful Vitality, and a crew consisting of San'Shyuum Captain Vervum L'kosur, communications officer S'Prog, and weapons officer Mleer, Sangheili Trok 'Tanghil, Vil 'Kthamee, Ziln 'Klel, and Loquen 'Nvong, and the Huragok Floats Near Ceiling. The corvette then departed for Janjur Qom.
• Growing distrustful of Ussa, Salus 'Crolon and 'Drem begin to conspire against the Refuge's leadership. Tersa 'Gunok refuses to join them, but becomes inadvertently involved with the conspiracy nonetheless.
• Vengeful Vitality arrives at the Reskolah region of Janjur Qom and a team is sent to the planet's surface, led by the Prophet of Inner Conviction. Upon arriving at the grotto of the Great Transition, the group retrieves a Luminary and a device. Loquen and Vervum betray the rest of the team, upon the orders of the Minister of Anticipatory Security. However, due to the intervention of Vil and Floats Near Ceiling, the others escape while Vervum and Loquen are killed or captured by the Stoics.
• Tersa becomes infatuated with Lnur 'Mol, and the two walk together in Ussa's Garden. They overhear 'Crolon and 'Drem attempt to convince two others to join their secret rebellion, but Tersa and Lnur are spotted. The two manage to outrun 'Crolon and 'Drem, but the latter two falsely claim that Tersa and Lnur are conspiring against Ussa.
• Covenant forces discover the location of the Ussan Sangheili rebels. Former Hierarch Qurlom delivers the news in the middle of the Prophet of Inner Conviction's "trial" in front the other Hierarchs. Inner Conviction is sent to lead a fleet to the Refuge while the Minister of Anticipatory Security is demoted.
• A Covenant fleet led by the Prophet of Inner Conviction arrives at the Refuge to destroy the last resistance to the Writ of Union. The Prophet secretly contacts Ussa to try to get him to surrender, but Ussa rejects. After a brief battle between Ussan Sangheili and boarding Covenant Sangheili and Sentinels, Ussa contacts Inner Conviction and tells him to pull back his forces or they will perish with his soldier when he destroys the shield world. Amazingly, he does just that, although he and other Ussans survive in separate sections. The Prophet of Inner Conviction decides not to look for survivors and returns to High Charity in partial failure once more.

• The Covenant makes first contact with the Lekgolo on Te in the Svir system while searching for Forerunner artifacts. The Covenant declares war on the species and the Taming of the Lekgolo begins upon discovering that the Lekgolo have devoured a majority of the Rings of Te—the gas giant's artificial planetary rings built by the Forerunners.

• During one of the first Ages of Conversion, Covenant forces make first contact with the Lekgolo on Rentus, a moon of the planet Te. They discover that many of the Lekgolo worm colonies have literally devoured Forerunner artifacts and installations, while others eat everything except Forerunner installations. The Lekgolo initially prove difficult to defeat because of their ability to combine into the powerful Mgalekgolo, however due in part to their superior spaceship technology the Covenant are able to ally with and tame the useful Lekgolo, and exterminate the relic-destroying colonies in what will come to be known as the Taming of the Hunters. The compliant Lekgolo are incorporated into the Writ of Union in 784 BCE.

• In 648 BCE, the San'Shyuum homeworld of Janjur Qom is allegedly destroyed by a natural stellar collapse. The construction of the Covenant capital city and mobile space station High Charity is also completed this year.

Globalization era

• In The Battle of Thermopylae of 480 BC, an alliance of Greek city-states fought the invading Persian Empire at the pass of Thermopylae in central Greece. Vastly outnumbered, the Greeks held back the massive army of Persians for three days in one of history's most famous last stands.

A small force led by King Leonidas of Sparta blocked the only road through which the massive army of Xerxes I could pass. After three days of battle, a local resident named Ephialtes betrayed the Greeks by revealing a mountain path that led behind the Greek lines. Dismissing the rest of the army, King Leonidas stayed behind with 300 Spartans and 700 Thespian volunteers. The Persians succeeded in taking the pass but sustained heavy losses, extremely disproportionate to those of the Greeks.

The fierce resistance of the Spartan-led army offered Athens invaluable time to prepare for a decisive naval battle that would determine the outcome of the war. The subsequent Greek victory at the Battle of Salamis left much of the Persian navy destroyed and Xerxes I was forced to retreat back to Asia, leaving his army in Greece under Mardonius, who met the Greeks in battle one last time. The Spartans assembled at full strength and led a pan-Greek army that defeated the Persians decisively at the Battle of Plataea, ending the Greco-Persian War and with it the expansion of the Persian Empire into Europe. This war was shown by Deja on the first day of Spartan training.

• The Yanme'e; a tier 4 civilization, are incorporated into the Covenant as a slave race.

• In 1342, the Covenant discovers the Kig-Yar. Although the Kig-Yar initially attempt to resist absorption into the alliance, they quickly recognize that they are facing a superior force and submit, taking on the role of explorers and traders (and often thieves and smugglers). The Kig-Yar are also motivated by the potential trade and wealth the Covenant can provide.

• In 1552, the San'Shyuum began developing technologies that could increase their life spans.

• The first human-made nuclear weapons are used against an enemy, when the United States drops two atomic bombs on the empire of Japan.
• The end of World War II, which was one of the bloodiest and most expensive wars in human history up to that point.
• The United Nations is formed on Earth at the end of World War II. The UN eventually forms the UNSC in the 2100s, but the UN begins embarking on military and security operations as early as the 1950s. Fifty-one nations originally signed the UN Charter, which governed the "global association of governments facilitating co-operation in international law, international security, economic development, and social equity." By the beginning of the 21st century, practically all the nation-states on Earth are members of the United Nations.

• David George and Aaron Elliot found the "Society of the Ancients".

• Margaret Efendi starts her beekeeping hobby with a single beehive.

• • Margaret Efendi buys her second beehive and founds Margaret's House of Bees.