Battle for Earth

"We ran from them. They followed. We thought they'd never find us... we were wrong."

- Cortana

The Battle for Earth, also referred to as the Earth Sustained Defense Campaign, was one of the largest, bloodiest and latest engagements fought between the Covenant and the forces of the Unified Earth Government (primarily those of the United Nations Space Command), at the end of the approximately twenty-seven year-long Human-Covenant War, which took place on and above the planet Earth from October 20 to not before December 3, 2552. It was one of the most important battles of the war, as the fate of humanity depended on the survival of its homeworld and seat of its government.

Though the invasion took place on a global scale, the most significant conflicts occurred in the East African Protectorate in the form of three battles fought within and between the cities of Mombasa and Voi, collectively referred to as the first, second, and third battles of Mombasa. The conflict began when the Fleet of Sacred Consecration, under the command of the Prophet of Regret, arrived on October 20 with intentions of traveling through the portal that a luminary in its possession pointed to. This move was made without the consent of the other two Hierarchs and in ignorance regarding the status of this planet as humanity's homeworld. Faced with the full might of the UNSC Home Fleet, it was not long before Regret's flagship fled to Installation 05. Soon after this, the Prophet of Truth initiated his plans to replace Sangheili with Jiralhanae and assume control over the entirety of the hierarchal triumvirate. Additional fleets, led by Jiralhanae, appeared in the system and quickly assumed control of all local Covenant forces by killing all Sangheili.

At this point, the fight for Earth began in earnest. Smaller battles were waged all across the world, from the UEG capital of Sydney, Australia, to Cleveland, URNA, to Havana, Cuba, and to Mount Erebus, Antarctica and multiple other locations. By November 17, most of the Home Fleet had been obliterated. It was on this date that the Prophet of Truth himself, aboard the Forerunner Dreadnought and with Spartan-117 in tow, arrived and headed straight for the Excession, by then fully excavated. Upon interfacing with the keyship, the portal was activated and a large contingent of the Covenant fleet departed through the Portal with the intention of activating the Halo Array from the Ark. Almost immediately after this, the Flood arrived aboard a captured, which crashed down in the town of Voi. The Fleet of Retribution, allied with the UNSC against Truth, was permitted to glass a large portion of Africa to prevent the parasite's spread. With the threat from the Flood dealt with and the bulk of Covenant forces gone, at least one UNSC frigate accompanied the Fleet of Retribution in pursuit of Truth. The remainder of UNSC forces remained behind to defend Earth from an expected full-scale Flood invasion and also began a major counteroffensive to eliminate all Covenant that remained.

Background
The Human-Covenant War was a decades-long conflict wherein the Covenant hegemony was determined to exterminate all of humanity at the behest of its three Hierarchs, who falsely considered humans as representing the living embodiment, and thus discreditation, of their religion's gods at the time of their discovery. Also a goal of the empire, from long before first contact with humanity, was the location and activation of the Halo rings. In the aftermath of the Fall of Reach, the UNSC began to pull the majority of its forces back to Earth, with most units assigned to defend Earth's six tether cities. The Prophet of Regret learned "Erde-Tyrene" held a portal which led to the Ark and the Prophet of Truth simultaneously discovered the planet's location through other means.

Formation of the Home Fleet
From May 14–19, 2552, UNSC forces in the Earth Defense Coordination Zone were placed at maximum readiness levels and all warships with magnetic accelerator cannons self-deployed or towed to rally points. Cairo Station was established as flag headquarters. On September 5, 2552, all remaining naval forces were consolidated into a single command grouping: the UNSC Home Fleet. Fleet Admiral Joseph Harper was appointed senior flag officer and given primary administrative and tasking authority over all assets in the Sol system under emergency directives authorized by UNSC High Command and approved by the UEG Security Council. Remaining expeditionary and defense fleets retained administrative control over their battle groups, though all type commands were dissolved.

Earth compromised


The Prophet of Truth discovered the location of Earth after the Fall of Reach, but withheld knowledge of this discovery from the rest of the Covenant leadership. To attack the human homeworld, he ordered an assault fleet to secretly assemble at Unyielding Hierophant station in the Tau Ceti system. The fleet would overwhelm Earth's defenses in a single decisive strike. The fleet was discovered by the UNSC AI Cortana and preemptive strike was led by Vice Admiral Danforth Whitcomb and a SPARTAN-II, strike team, which successfully destroyed Unyielding Hierophant and almost the entirety of the assembled fleet, some five hundred ships. Earth was granted a small reprieve.

The Prophet of Regret also independently learned of the location of Earth as the location of a Forerunner artifact, the Portal leading to the Ark. This revelation came after long study by stewards of a Forerunner luminary taken from the moon, Meridian, in 2551. Not being privy to Truth's information, Regret set off to uncover the artifact without any knowledge that Earth was the humans' homeworld. Regret unknowingly led his small fleet, a mere two assault carriers and thirteen battlecruisers, straight into Earth's formidable defenses. Truth belatedly learned of Regret's expedition to Earth, and dispatched a large Jiralhanae-led fleet to reinforce the attack. They arrived mere hours after Regret had fled.

Arrival Regret's fleet
"Something's not right. The fleet that destroyed Reach was fifty times this size!"

- Fleet Admiral Terrence Hood

The High Prophet of Regret's fleet was detected near Jupiter's moon Io, as a series of slipspace "whispers". Probes were sent to investigate, but shortly afterwards the Covenant fleet exited slipspace near Earth, just outside the killzone of the planet's orbital defense platforms. UNSC forces went to TACCON Alpha 2. Fleet Admiral Harper ordered his battle group to attack, but quickly received new orders from Fleet Admiral Terrence Hood to fall back and defend the ODPs. Having expected an overwhelming enemy offensive in the style of the Battle of Reach, the relative weakness of the attack puzzled the defenders.

Orbital Defense
The assault carriers converged on the battle cluster including Athens Station, Cairo Station and Malta Station. The ODPs opened fire as the enemy entered range. Covenant troops boarded the stations, intending to demolish them with an antimatter charge each. As each bomb was planted the Covenant withdrew. Athens and Malta were demolished in quick succession. Cortana, aboard Cairo, deduced the nature of the threat and John-117 was dispatched to prevent the same fate from befalling Cairo.

Cortana directed the SPARTAN-II to the bomb's location in Cairo's fire control center. En route to the bomb, John-117 rescued Commander Miranda Keyes and allowed her to board. The frigate departed Cairo to join the fray.

Meanwhile, Harper's Fifth Fleet continued to engage the Covenant task force in Earth orbit, sustaining huge losses in the wake of the Covenant's superior firepower but still prevailing through sheer numbers against the unusually small Covenant force. However, even as their escorts were effectively routed by the UNSC, the two assault carriers pushed onward, bypassing much of the already battered human fleet even as they too came under fire.

The two assault carriers began to break through toward Cairo. Cortana directed Cairo's MAC against the Solemn Penance, but the ship did not stop to engage and instead made directly for New Mombasa on the surface. Admiral Harper led the attack on the second carrier and depleted its shields. Keyes volunteered to attack the carrier immediately, but Hood was unwilling to pit a single frigate against so large a target.

The solution to the second carrier came from an unexpected angle. John-117 and Cortana managed to defuse and capture the Covenant antimatter bomb aboard Cairo, and the Spartan volunteered to go EVA and personally plant the bomb on the last carrier. With Lord Hood's approval, John-117 leapt out of an airlock with the bomb using only the initial explosive decompression for impulse. Longsword interceptors opened a breach in the carrier's hull and allowed the Spartan to infiltrate and plant the bomb internally. The detonation destroyed the ship. John-117 escaped using the same means he had arrived and free fell to the UNSC In Amber Clad.

Earthside
"Dear humanity, we regret being alien bastards, we regret coming to Earth, and we most definitely regret the Corps just blew up our raggedy-ass fleet!"

- Avery Johnson commenting on Regret's message.

Regret's carrier came to stop over New Mombasa in the East African Protectorate and deployed troops into the city and the surrounding area. UNSC high command wished to discover why the Covenant were landing only in Mombasa, and John-117 was ordered to capture Regret for interrogation. The Spartan deployed with marines and ODST in a trio of Pelicans from the near the city. The dropships were shot down by a Covenant Scarab in Old Mombasa. John-117 and the survivors regrouped and pursued the walker to NM 105E, and across the bridge to New Mombasa Sector B. The Scarab was eventually trapped and destroyed at the end of a canal. Covenant forces started to withdraw to the carrier for slipspace departure.

In orbit the Home Fleet began deploying ODSTs to Mombasa in SOEIVs, intending to board the the carrier and capture the Prophet of Regret. One Squad, Alpha-Nine, deploying from the and led by Gunnery Sergeant Edward Buck, was diverted by ONI to secure the city's infrastructure AI.

Regret's means of escape took the UNSC by surprise. The carrier initiated a slipspace jump while still over the city. The UNSC In Amber Clad quickly recovered John-117 and the light frigate along with, and  followed in the fleeing ship's wake. The slipspace rupture severely damaged the city and generated an EMP. Many ODSTs had not yet landed when the carrier escaped and were caught in the EMP and blast. Drop pods were disabled in flight and plunged into uncontrolled freefall. Those who survived the blast were scattered across the city.

Arrival of Truth's Fleet
Immediately following the slipspace event, Jiralhanae forces loyal to the High Prophet of Truth, who had embedded said troops into his political Rival Regret's fleet, enacted their leader's orders. The Jiralhanae violently displaced their Sangheili commanders both ground-side, and in orbit, the beginning of Truth's plan to place the Jiralhanae as the Covenant's primary warrior race. Multiple additional Jiralhanae led-Covenant ships sent by Truth also began to arrive in the Sol System, joining the remains of Regret's fleet in the assault upon Earth.

Surviving UNSC forces in the city, aided by the New Mombasa Police Department, continued to resist, but were eventually overwhelmed. The Covenant began glassing Mombasa and the surrounding area, uncovering the Portal to the Ark. Captain Dare and her ODST squad managed to secure the city's infrastructure AI and escape before the city fell to the enemy.

Around this time, Covenant forces also attacked Cairo, Egypt and Berkeley, URNA.

Covenant occupation
The battle spread over the globe in the following weeks. The diminishing UNSC Home Fleet, in conjunction with the Second, Seventh, and Sixteenth Fleets, remained to contest Earth orbit against numerous arriving Covenant vessels, but the Covenant continued to raid the surface in search of Forerunner artifacts, mostly concentrating in east Africa.

A Second Battle of New Mombasa would take place over seven days before the end of October.

The Spartan Blue Team, consisting of Frederic-104, Linda-058, and William-043, were constantly engaged for the first two weeks. They repelled enemy ships in orbit in numerous zero-gee operations whilst on the surface they neutralized Covenant excavations, first on Ross Island in Antarctica, and then underwater off the Yucatan Peninsula. On November 3, they were deployed to Havana, Cuba, where they stole the enemy destroyer Bloodied Spirit, and destroyed another destroyer and the Centennial Orbital Elevator. They subsequently redeployed aboard the stolen ship to the Forerunner shield world Onyx to aid Dr. Catherine Halsey, the creator of the SPARTAN-II program.

The UNSC's loss of their garrison on Mars following the Battle of Mare Erythraeum led to a dramatic increase in Covenant force deployments on Earth, worsening the attack on the planet. Shortly after the loss of Mars, Covenant also invaded the city of Cleveland on Earth, looking for an artifact known as the "Key of Osanalan". The Key turned out to be a hoax perpetrated by Colonel James Ackerson; this attack was ultimately repelled due to the Colonel's act of self-sacrifice, and that of his civilian brother, Ruwan. Though the Martian valiant defense forces were eventually crushed, they are credited for delaying Covenant forces from pressing their siege on Earth.

Sydney, Australia was one of the cities invaded by the Covenant during the engagement. Though the city suffered heavy damage by Covenant bombardment, the UNSC's HIGHCOM Facility Bravo-6 remained undamaged.

Near the conclusion of the Battle of Installation 05, the Prophet of Truth departed High Charity, near Halo Installation 05, in the Forerunner Dreadnought on November 3, arriving at the Sol system on the 8th. The prophet sought to activate the Ark, fire the Halo Array, and begin what he thought would be the "Great Journey". Unbeknownst to the Covenant, John-117 had stowed away aboard the ship.

On November 10, Covenant forces began to excavate and occupy built-up positions centered around Free-fire Area OZONE in Arizona, URNA.

Whilst on Installation 05, Commander Miranda Keyes, Sergeant Major Avery Johnson, and Arbiter Thel 'Vadam learned of the Prophet of Truth's intentions and departed the installation after the Dreadnought while Rtas 'Vadum and the Sangheili under his command stayed behind on Installation 05 in order to quarantine and glass the Halo ring as well as quarantine High Charity in order to stop the escape of the Flood and the Gravemind from both the Halo and the city. Upon arrival at Earth on or just before November 15 with a Seperatist vessel, they took up station in an old military base, Crow's Nest, near Voi, and waited for John-117 to arrive.

The Keyship arrives
"Fleet Admiral Terrence Hood"

The Forerunner Dreadnought arrived at Earth on November 17, spearheading the final contingent of Truth's forces. The remaining loyalist naval forces of the High Charity defense fleet breached the Lunar perimeter, utterly demolishing the remnants of the UNSC Home Fleet at the cost of most of the overwelming Covenant fleet. The subsequent bombardment caused "extreme" casualties. As the Dreadnought entered Earth's atmosphere, John-117 left the ship by leaping off during re-entry and crashing into the East-African jungle. By this time the Covenant had set up heavy AA batteries and other defenses near Voi and in the surrounding area to protect their work at the Portal.

During Spartan-117's re-entry, a pair of ODSTs used a laser designator during a battle in Sector Six (near the Pakistan-Afghanistan boder) to track the Spartan's fall. The data made it easier for Sergeant Johnson and Thel 'Vadam to locate the Spartan. After making their way through the jungle, they were extracted by a dropship, despite Covenant resistance, and taken to Crow's Nest. The Covenant tracked them back to the base, however, and launched an attack.

Commander Keyes proposed to destroy the Covenant anti-air defenses at Voi, allowing low flying frigates to strike the Forerunner Dreadnought now landed on the Portal. Fleet Admiral Terrence Hood had only a few frigates left, but was willing to commit to the risky plan with John-117's recovery.

Just before the UNSC offensive began, the Covenant attacked Crow's Nest. Miranda Keyes evacuated and destroyed the base with a bomb before it could be occupied. John-117 barely managed to escape the destruction of the facility but met up with Gunnery Sergeant Reynolds and set out in Warthogs on Tsavo Highway to head for Voi, as did scattered UNSC forces, engaging Covenant heavy vehicles along the way.

At Voi, the UNSC broke through Covenant defenses, as John-117 and Thel 'Vadam disabled a Covenant AA battery. With the path to the Portal cleared, Fleet Admiral Hood ordered at least seven frigates and multiple Longswords to attack the Forerunner Dreadnought. Despite MAC fire, the enemy ship remained intact and was able to activate the Portal. The Dreadnought and the surrounding Covenant ships departed Earth through the resulting Slipspace portal. Covenant battlenet cohesion broke following Truth's departure, allowing UNSC forces in the southwest URNA to begin a major counteroffensive as part of their ongoing campaign.

The Flood on Earth
"Quickly! Let us find their ship. Make short work of this abomination!"

- Thel 'Vadam

While the battle for Earth raged, the Covenant had been attempting to maintain a quarantine of the Flood-infested High Charity and Installation 05. The Flood-controlled Indulgence of Conviction escaped and arrived at Earth as the Prophet of Truth departed through the Portal. The ship crashed in Voi and began infesting the area. John-117 and Thel 'Vadam quickly made for the crash site intending to overload the ship's reactor. The explosion would destroy the city but would hopefully stop the spreading infestation as well.

Sangheili ships, led by Fleet Master Rtas 'Vadum aboard the assault carrier Shadow of Intent, arrived in pursuit of the Flood. The Sangheili believed Cortana was aboard the Flood ship; Rtas 'Vadum could give his own troops and the UNSC only a little time to recover the AI before Voi and the surrounding area were cleansed by glassing. John-117 found the small storage device containing the AI; he entrusted to 343 Guilty Spark for repairs and they were extracted by Phantom to Shadow of Intent.

Thel 'Vadam convinced Rtas 'Vadum to exercise restraint when glassing. Thus, only an area of Africa was glassed instead of a much wider area.

Shortly after the initial skirmishes with the Flood, the Flood-infested High Charity jumped out of slipspace further out in the Sol system. Shortly after discovering the presence of the Portal at Voi, the Gravemind conducted an arcane bridging maneuver allowing it to transport the former holy city to the Ark from the vicinity of Mars rather than physically accessing the portal on Earth; the human homeworld thus escaped further Flood contamination.

Mopping up remaining Covenant forces
"Terrence Hood"

Admiral Hood and Commander Keyes joined John-117, Thel 'Vadam, and Rtas 'Vadum aboard Shadow of Intent where 343 Guilty Spark repaired Cortana's damaged storage device. The device contained only a message from the AI; it warned them that the Flood-infested High Charity was en route to Earth, but that beyond the Portal there was a solution to the Flood without firing the Halo Array.

Admiral Hood was determined to make his stand against the Flood on Earth. The Sangheili believed this to be foolish; there was little hope Earth could withstand a Flood spore, never mind a full Flood invasion, and they decided to place faith in Cortana and journey beyond the Portal. John-117 and Keyes convinced a weary Hood to allow them, and a UNSC task force to accompany the Sangheili.

The final stand Hood expected never came; the next day, High Charity and the Flood arrived in the Sol system, but instead performed a Slipspace jump from Mars orbit to Installation 00, an action that spared Earth from a second contamination. It was at the massive installation that the Flood and the remnants of the Covenant were ultimately defeated by the UNSC and Sangheili three weeks later, bringing an end to the war that nearly extinguished the human race.

With the majority of Truth's forces now bound for the Ark, the remainder of the Covenant was on Earth as several fortified themselves in Arizona, URNA. On December 3, Admiral Harper of the Fifth Fleet initiated Operation: MARSH FLASH, which eradicated clusters of Jiralhanae leadership attempting to activate an artifact here. The UNSC was then finally able to repel or wipe out the remaining Covanant invader forces on the planet and the system, effectively bringing an end to the invasion. Despite suffering enormous military and civilian losses, the UNSC retained control of Earth. Marines involved in mopping up Jiralhanae holdouts employed the "Rex" VISR system.

Rebuilding and Rebirth


On March 3, 2553, a special ceremony on a hill over looking the Portal at Voi was held to honor the end of the war and those who had fallen.

The rebuilding of Earth's infrastructure had begun in earnest as early as January 2553 in Sydney. Project Rebirth, an organized effort to rebuild also took place in Aranuka and Mombasa took place at some point, with works in Aranuka being done by 2558.

Engagements
The battle of Earth had numerous engagements across the planet. Kenya, Cleveland, Havana, and the Southewestern URNA were battlefields. Fighting also took place at Sydney, Cairo, Diego Garcia, Aranuka, the Yucatán Peninsula, Mount Erebus, and Berkeley.

Luna, Earth's moon was also attacked.

Participants
Due to the prominence of Earth, and what had transpired prior to the battle, Earth possessed numerous UNSC assets. They clashed with several waves of Covenant forces.

Production notes
Many fans, as well as Halopedia, used to regard the Battle of Earth as two separate battles. Namely, the "First" was believed to comprise the events of Halo 2 and the "Second" was thought to cover the events of John-117's return at the beginning of Halo 3. Later sources have established that Truth's reinforcements arrived just hours after Regret fled, indicating that the "two" battles were one and the same. However, the Halo Encyclopedia (even the 2011 revised edition) lists them as two separate battles; this is one of several elements of the Encyclopedia that is seemingly lifted from this wiki.

List of appearances

 * Halo: First Strike
 * Adjunct
 * Halo 2
 * Halo Graphic Novel
 * Second Sunrise Over New Mombasa
 * Halo: Ghosts of Onyx
 * Halo: Landfall
 * Halo: Combat
 * Halo: Last One Standing
 * Halo: Uprising
 * Halo 3
 * Halo 3: ODST
 * Sadie's Story


 * Halo: Evolutions - Essential Tales of the Halo Universe
 * Palace Hotel
 * Halo: Glasslands
 * Halo 4
 * Halo 2: Anniversary
 * Halo: New Blood
 * Hunt the Truth
 * Halo: Spartan Strike
 * Halo Mythos
 * Halo: Envoy
 * Halo: Legacy of Onyx
 * Halo: Official Spartan Field Manual