History of The Planet Earth Halo

"Fight for her.”

— UNSC Pillar of Autumn Bulletin board poster of Earth

Earth is the third planet of the Sol system, and one of its four terrestrial worlds. Homeworld of the human species, Earth has been at the forefront of galactic history, from encounters with the Precursors[8] to the end of the Covenant Empire. Inhabited long ago by a prehistoric interstellar human government conquered and dissolved by the Forerunners, Earth is currently the capital world of the Unified Earth Government.

Earth was possibly the most populated planet of the human space territories. For a significant amount of humanity's history, it was their only known place in the universe to support life.

History

Prehistory

The Earth first formed about 4.6 billion years ago, and gave rise to the first single-celled organisms about 3.9 billion years ago. About 200,000 years ago, the ancestors of modern humans, Homo Sapiens, evolved in Africa. Indigenous to Eastern Africa, they gradually spread across the entire planet. Eventually, the humans, originally consisting of groups of hunter-gatherers, began to develop into civilizations.

Human civilizations gradually became more and more complex, and eventually, possibly through contact with the Forerunners, humanity discovered spaceflight and spread across the Orion Arm of the Milky Way galaxy. After being defeated in a war against the Forerunner civilization, the humans were exiled back to Earth, with their species devolved and splintered into multiple subspecies and their culture degrading back to a primitive state for millennia.

After the war with the Forerunners, Earth and humanity came under the charge of the The Librarian, a Forerunner Lifeshaper who helped the humans slowly work towards rebuilding a primitive civilization. Remnants of their former technology, such as steam power and hot-air balloon flight, were re-learned under her care but later forgotten after the firing of the Halo Array.

Forerunner-Flood war

Near the end of their war with the Flood, the Forerunners built a machine to generate a slipspace portal to the Ark in Africa. They also indexed the human species as a part of their Conservation Measure to preserve life in the galaxy after the activation of the Halo Array. After the array's activation, human life was planted back on Earth, where it successfully re-developed.

Interplanetary colonization and conflicts

By 2080, humanity's national governments, under the auspices of the United Nations, had begun to establish colonies on the other planets in the Sol system. However, expansion did not come without problems. In the mid-22nd century, two major dissident factions emerged; the neo-communist Koslovics and fascist Frieden, which began to battle one another and the United Nations.

In March–June 2160, Jovian Frieden secessionists attacked members of the United Nations on the moon Io, which led to three months of fighting between the Earth military and Jovian Frieden forces. National governments began to support their own colonies which sparked proxy wars off-planet, leading to tension and militarization on Earth. In 2162, armed conflict ripped through South America, starting the Rain Forest Wars, as Koslovic, Frieden, and UN forces all clashed over ideological differences, sparking additional conflicts off-planet. In December of 2163, the three factions clashed, this time on Mars. This was the first extraterrestrial use of Marines, who launched lightning raids on Koslovic positions, permanently affecting military doctrine for centuries. In 2164, UN forces began a massive military build-up and began the first true interplanetary war. The forces of the fledgling United Nations Space Command were significantly bolstered by a massive propaganda campaign running on the victories on Mars and over the next six years took back the Sol system and drove the dissident factions to destruction. Now with a massive military with no enemy to fight, overpopulation, famine, and a collapsing economy, the newly unified Earth faced an uncertain future.

It was not until 2291 that this problem was solved when researchers created the Shaw-Fujikawa Translight Engine which enabled superluminal travel by allowing access to an alternate domain known as Slipstream Space. In 2310, the UNSC unveiled their first line of colony ships and the best and brightest from both civilian walks of life and the military set out to form the Inner colonies. This eased the overpopulation problem upon Earth which became the capital of the Unified Earth Government, while the inner colony of Reach would later become the headquarters of the UNSC.

The Insurrection and the Human-Covenant war

Humanity would enter a period of peaceful stability for the next two hundred years, until civil unrest began to spread in the Outer Colonies, with various groups seeking secession from Earth and the UEG. The scale of the unrest would steadily rise, eventually becoming a major threat by 2517.

All this was suddenly and violently rendered a moot point when a single alien ship made an unprovoked attack on the colony of Harvest, humanity's first encounter with an alien civilization - the Covenant. Over the next twenty-seven years, humanity would wage a brutal war for survival, losing hundreds of colonies, including all of the Outer Colonies in 2536; and on 31 August 2552, the UNSC's largest military installation, the planet Reach, was destroyed by the Covenant. During the entire course of the conflict, the UNSC followed the Cole Protocol, which declared that no UNSC vessel targeted by the Covenant was to retreat to Earth, as a means of ensuring the secrecy and security of the planet's location. In nearly twenty-seven years of galactic warfare, the Covenant never succeeded in determining the location of Earth through the measures taken under the Cole Protocol. However, by September 2552, Earth was humanity's last major stronghold in its war against the Covenant.

Despite the effectiveness of this law, on 20 October 2552, the Covenant launched their first attack upon Earth, rendering the Cole Protocol moot and initiating the final confrontation between UNSC forces and the Covenant.

Pre-Battle of Earth

Prior to the Covenant invasion of Earth, there had been a suppressed influx of information by ONI, resulting in people going about their normal lives even up until the attack. Several fleets were brought to Earth. Some like the Fifth Fleet were merged with the Home Fleet in a special command grouping.[16] Other fleets brought to Earth include the Second Fleet, Seventh Fleet, and the Sixteenth Fleet.[17] The 6th Battle Group[18] along with large amounts of Marines, Army Troopers, and ODSTs present, five SPARTAN-IIs were also brought to or were near Earth.

Battle of Earth

On October 20, 2552, the first Covenant forces entered the Sol system. A Covenant expeditionary force consisting of 13 CCS-class battlecruisers and 2 CAS-class assault carriers arrived in system, first detected around Io, the third largest moon of Jupiter. After the existence of the Covenant presence was confirmed by probes, the UNSCDF forces went to full alert. The option was taken to wait for the Covenant forces to come to them rather than let Fleet Admiral Harper launch a counterattack.

The Covenant began to work on punching a hole through the orbital defenses by taking out the stations in the battle cluster above the Mediterranean Sea via bombs planted by boarding parties. After the Covenant fleet attempted to rush through the newly formed gap the UNSC fleet annihilated them, destroying most of the Covenant battlecruisers but failing to destroy the assault carriers. One of the assault carriers was successfully destroyed by SPARTAN-II John-117 but the other, commanded by the High Prophet of Regret assaulted the city of Mombasa in Kenya.

Groundside, the Covenant assault carrier had already deployed its ground forces and occupied the city. The Covenant ground forces immediately constructed defense emplacements and structures to reinforce their newly acquired sites against the counter-offensive UNSC forces. The UNSC In Amber Clad was the first UNSC ship to respond to the Covenant occupation. The ship sent in their complements consisting of SPARTAN-II John-117, Sergeant Avery Johnson and elements of the 7th Orbital Drop Shock Trooper Battalion.[19] The Covenant were subsequently dislodged from Old Mombasa and, following the destruction of a Scarab, from New Mombasa as well.[19][20] The High Prophet of Regret eventually ordered a general retreat and had his assault carrier initiate a slipspace jump while still over the city. The In Amber Clad followed in the carrier's wake, while the city was left in chaos.

Prior to the slipspace event, a contingent of ODSTs were dropped from the UNSC Say My Name to assist the In Amber Clad's counter-offensive efforts. The slipspace rupture prevented the assist from taking place, plunging the ODSTs into uncontrolled freefall and scattered across the city. However, one particular squad of ODSTs survived and continued their operation in securing the city's infrastructure AI. During the operation, the squad witnessed the arrival of a larger Covenant fleet after escaping the city.

The Covenant returned in force following the Prophet of Regret's abortive attack and a Covenant assault forces succeeded in penetrating the orbital defenses. At Mount Erebus, the sea floor off of the Yucatan Peninsula, and at the Centennial Orbital Elevator in Havana, Cuba, the Covenant were stymied by three SPARTAN-II's, only to have those SPARTAN-IIs get re-deployed to Onyx. The Covenant deployed their forces all across Earth, striking at major cities such as Cleveland, Ohio; but this attack too was repulsed through the efforts of ODST forces and the self-sacrifice of Colonel James Ackerson. However, UNSC forces were unable to repulse and route Covenant landings in Kenya. After breaking Earth's space defenses, the Covenant bombarded Earth in Eastern Africa. The Covenant eventually succeeded in eradicating Mombasa and uncovering their primary target: The Artifact.

The arrival in-system of John-117 in a Covenant-controlled Forerunner dreadnought, freshly escaped from the Battle of Installation 05, was unexpected. John-117 disembarked from the dreadnought in Earth's atmosphere, later recovered by Marines and taken to Crow's Nest. With the aid of Thel 'Vadam, Commander Miranda Keyes, and Sergeant Avery Johnson, John-117 breached the Covenant anti-air defenses near the excavated artifact, clearing the way for an aerial strike on the Dreadnought powering it. The strike was unable to disable the device or prevent the Prophet of Truth from traveling through the portal. After a brief intervention by the Flood, a joint Separatist/UNSC force departed through the portal in pursuit. This series of events saw the complete departure of the Covenant from Earth as they ventured forth to Installation 00, where they would finally be crushed by the UNSC and their Separatist allies.

Post-War Period

Following the victory at the Battle of Earth and the Battle of Installation 00, the Human-Covenant war ended in March 2553. Many of Earth's cities were left in ruins and the planet's population was sharply reduced as a result of the Covenant invasion. With the war's end and the departure of the Covenant separatists to their respective homeworlds, the UNSC began to rebuild the extensive damage inflicted upon Earth's infrastructure and human population. Following the end of the Human-Covenant war, Earth saw an influx of refugees from former Covenant species, who were walled off in "conclaves."

On July 25, 2557, Shadow-of-Sundered-Star moved into targeting range in the Mantle's Approach with the Composer and proceeds to compose the residents of New Phoenix. John-117 and with the help of Battlegroup Dakota, flew a Broadsword into the ship. There he confronted the Didact and used a Pulse grenade to send him through a slipspace portal to Installation 03. John then detonates a HAVOK Tactical Nuclear Weapon, destroying the Composer and the ship. This was then dubbed the New Phoenix Incident and the city was placed under quarantine until eight months later on 24 March 2558.

In 2557, only six months after the New Phoenix Incident, an unknown Sangheili refugee attempted to detonate a HAVOK Tactical Nuclear bomb in Rio de Janeiro, but was apprehended by Fireteam Majestic before he could do so.