2160 - 2200

This period in human history was marked by a series of brutal conflicts between various governments and factions in the Sol System. Conflicts of particular historical importance included the Jovian Moons Campaign, The Rain Forest Wars, and a series of clashes on Mars.

As overpopulation and political unrest on Earth increased, a number of new political movements formed. The most noteworthy dissident movements of the period were the "Koslovics" and the "Frieden" movement. The Koslovics—supporters of neo-Communist hardliner Vladimir Koslov—sought a return to the glory days of Communism and the elimination of corporate and capitalist influence, particularly in orbital facilities and off world colonies.

The Frieden movement was a resurgence of fascism, springing from anti-Koslovic sentiment that had taken root in the Jovian colonies (largely backed by Unified German Republic corporations, frequent targets of Koslovic "workers' crusades"). "Frieden" literally means "peace"-in this case, they believed that peace could be achieved only once the "oppressors on Terra Firma" were eliminated.

2160 (March-June)

The Jovian Moons Campaign began. Jovian secessionist attacks on United Nations Colonial Advisors on the moon Io led to three months of fighting between the Earth military and Jovian "Frieden" forces. Though this was not the first armed conflict in our Solar System, it was easily one of the bloodiest, and is generally considered to be the spark of increased friction and miniaturization that followed.

The Jovian Moons Campaign escalated tensions, as Earth's national governments-many of which sponsored colonies within the system-began fighting proxy wars off-planet. As these proxy wars continued, tensions on Earth mounted, leading to a number of armed conflicts on Earth itself.

In a conflict that stemmed from the Rain Forest Wars, the three primary Earth factions clashed again, this time on Mars. A series of lightning strikes against Koslovic forces near the Argyre Planitia marked the first extra-terrestrial deployment of Marines. The campaign was an unqualified success. As a result, future military doctrine favored large contingents of Marines for ground assaults and ship-boarding actions.

A unified Earth government was formed in the wake of the conflicts of 216. Now, the victors were forced to deal with a less obvious but equally serious threat: overpopulation and a massive military that had no enemy to fight.

In the postwar period there were massive population surges and the overpopulation, coupled with the destruction and famine bred by the Rain Forest Wars, threatened to destabilize the economy.

A team of researchers, physicists, and mathematicians working in secret developed the Shaw-Fujikawa Translight Engine, a practical means of propelling spacecraft across vast interstellar distances. This new engine allowed ships to tunnel into "the Slipstream" (also called "Slipspace"). Slipspace is a domain with alternate physical laws, allowing faster-than-light travel without relativistic side-effects. Faster-than-light travel is not instantaneous; "short" jumps routinely take up to two months, and "long" jumps can last six months or more.

The SFTE generated a resonance field, which when coupled with the unusual physics of the Slipstream, allowed for dramatically shorter transit times between stars; however, scientists noted an odd "flexibility" to temporal flow while inside the Slipstream. Though no human scientist is sure why travel time between stars is not constant, many theorize that there are "eddies" or "currents" within the Slipstream-there is generally a five to ten percent variance in travel times between stars. This temporal inconsistency has given military tacticians and strategists fits-hampering many coordinated attacks.

The Earth government unveils the first in a line of colony ships; given conditions on Earth are deteriorating in the face of overpopulation, hitching a ride out to a colony becomes a highly attractive option. Additionally, the Earth government plans to attach military personnel to each colony, to help better utilize the massive (and expensive) standing fleets. Because FTL travel is still fairly new and expensive, colonists and military personnel face a stringent regimen of physical and mental testing. In theory, only the best-qualified citizens and soldiers are allowed to colonize "nearby" worlds. This is the birth of the Inner Colonies; typically Inner Colonials are-later in the timeline-considered the elite, the best and brightest.

The Odyssey is launched. The lead ship in the colony vessels, the Odyssey-laden with troops and terra forming gear-spearheads the colonization of a new world. This sparked the first wave of human expansion beyond the confines of the Solar System.

The colonization of the Inner Colonies was fully underway. There were 210 human-occupied worlds in various stages of terraforming, and the population burden across human-controlled space was largely stabilized.

Expansion continued at a rapid pace, and by 2490 human space encompassed more than 800 worlds throughout the Orion Arm of the Milky Way (ranging from fairly well-tamed planetary strongholds to tiny hinterland settlements). Outward expansion continued, and the Inner Colonies become a political and economic stronghold, though they relied heavily on raw materials supplied by the Outer Colonies.

During this period, the planet Reach (orbiting Epsilon Eridani, right on Earth's metaphorical doorstep) became the UNSC's primary Naval yard and training academy. Reach was a major producer of warships and colony vessels, as well as a training ground for covert operatives and Special Forces.

First rebel insurrection in Eridanus system.

The Eridanus insurrection is defeated by UNSC forces.

The structural system for the Pillar of Autumn is designed by Dr. Robert McLees at the Reyes-McLees Shipyards over Mars.

A geological survey team on Sigma Octanus IV finds rocks with odd compositions - these were introduced from meteor impacts roughly 60,000 years ago.

Second rebel insurrection in Eridanus system, led by Colonel Robert Watts, is suppressed by the UNSC in operation TREBUCHET. Watts is driven into the local asteroid belt.

A UNSC battle group consisting of one Destroyer (Heracles, Captain Veredi) and two Frigates (Arabia and Vostok) enters the Harvest system and discovers that everything on the planet has been completely incinerated and the surface melted down to glass. In orbit around the remains of the colony world is a single alien ship, which proceeded to attack the battle group, destroying both Arabia and Vostok and badly damaging the Heracles. Intercepted communications identify the enemy as The Covenant. The message "Your destruction is the will of the Gods... and we are their instrument" is broadcast in UNSC language.

The Spartans are divided into two teams: Red and Blue. John and the rest of Blue team (Linda and James), while on an orbital mission to ensure that a NAV database stays out of Covenant hands, end up onboard the Pillar of Autumn when she jumps away from the Reach system to evade Covenant forces. James is lost and Linda is mortally wounded, and the subsequent mission on Halo is left to the Master Chief to complete.

The Covenant take the surface of Reach, and Red team splits, one group to retrieve Admiral Whitcomb, while the rest hole up in ONI's Castle Base underground facility with Dr. Halsey. The Spartans receive parts of a MJOLNIR Mark V upgrade and new weapons, while Dr. Halsey learns of Colonel Ackerson's mysterious plans, plans that seem to involve "her" Spartans.