2160-2200

Early Conflicts:

This period in human history was marked by a series of brutal conflicts between various governments and factions in our Solar 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 offworld 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. [1]

2164

Interplanetary War:

UN-sponsored military forces began a pattern of massive buildups, culminating in the first real interplanetary war. After the successful Marine deployment on Mars, recruitment drives and propaganda tactics strongly bolstered UNSC (United Nations Space Command) forces. UN forces defeated Koslovic and Frieden forces on Earth, then began a systematic and dedicated drive to crush their remnants on the various planets they held throughout the system. At the conclusion of these brushfire conflicts, Frieden and Koslovic forces were defeated in the face of a massive, unified and very powerful UN military. [1]

2170

Expansion:

A unified Earth government was formed in the wake of these conflicts. 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. [1]

2291

Faster Than Light:

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. [1]

2310

First Wave:

The Earth government unveiled the first in a line of colony ships—and volunteers were in great supply. Conditions on Earth had deteriorated in the face of overpopulation, so hitching a ride out to a colony became an attractive option.

Each colony ship was assigned military personnel and escort ships to help better utilize the massive (and expensive) standing fleets that, in the collapse of armed dissent, were soaking up a great deal of funding and resources.

Because FTL travel in this period was still fairly new and expensive, colonists and military personnel faced a stringent regimen of physical and mental testing. In theory, only the best-qualified citizens and soldiers were allowed to colonize "nearby" worlds. This was the birth of the Inner Colonies. [1]

2362

The Odyssey:

The Odyssey launched on January 1, 2362. The lead ship in a fleet of colony vessels, the Odyssey—laden with troops and terraforming gear—spearheaded the colonization of a new world. This sparked the first wave of human expansion beyond the confines of the Solar System. [1]

2390

Inner Colonies:

By 2390, 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. [1]

2468

Harvest:

The colony of Harvest is established in this year by the UNSC Skidbladnir. The ship is eventually used for materials to build the colony, its power plant is used to power the capital city of Utgard. [3]

2473

UNSC Spirit of Fire:

The UNSC Spirit of Fire CFV-88 is constructed.  It is a Phoenix class colony ship that is later refitted into a warship. [4]