United Nations Space Command

The United Nations Space Command (UNSC) is the military, exploratory, and scientific agency of the Unified Earth Government (UEG) and has acted as the emergency governing body of the human race at large for a time.^[9] The UNSC was formed in the 22nd century, a time when remnants of old cultural ideologies clashed for supremacy in the Sol System. The UNSC served mainly as overseer of United Nations military operations in space. After initiating massive militarization propaganda throughout its off-world colonies, through the UNSC, the UN defeated Frieden and Koslovic insurgent forces in a conflict known as the Interplanetary War, which consisted of several side-battles that took place on Mars, the Jovian Moons and the South American rainforests. Although the Interplanetary War brought a great deal of suffering to both the colonial population and the residents of Earth, it also united most of humanity's military forces by the end of the 22nd century.^[10]

Prior to the Covenant attack on Harvest in 2525,^[10] the UNSC was stretched across human space. The most urgent concern was to contain the spread of the Insurrectionists, a violent resistance movement consisting of colonists who wanted independence from the Unified Earth Government. The UNSC fought constant battles in a loosely-defined civil war known as the Insurrection. In an attempt to help end the long-running war, the UEG commissioned the ORION Project and later the SPARTAN-II program, which created elite supersoldiers to combat the Insurrectionists. When the Human-Covenant War began and the alien invaders began destroying the Outer Colonies, these Spartans became humanity's best hope against the technological superiority of the hegemony. When the war began, the UNSC, which had been mired in controversy, became humanity's greatest protector. This allowed the UNSC to override civilian rule and establish itself as humanity's primary government. Although the Unified Earth Government was more open to step down, the Colonial Administration Authority, the arm of the UEG ruling over the colonies, resisted the UNSC's rise to power, and was stripped of its influence.^[9]

Near the end of the year 2552, Earth was the last remaining major human bastion: it too nearly fell under attack by the Covenant, succumbing to occupation. Near-crippled in the aftermath of the Fall of Reach, the UNSC led by Chairman Chief of Naval Operations Fleet Admiral Lord Terrence Hood, dedicated most of its remaining assets to the defense of the Sol System. The Human-Covenant War finally came to an end after the UNSC and the Sangheili Fleet of Retribution eliminated the Covenant leadership and destroyed the Flood threat.

In the aftermath of the war, the UNSC has upheld its alliance with the Swords of Sanghelios and eventually ceded political power back to the UEG. The UNSC is now experiencing a resurgence as it rebuilds humanity's war-torn domain and moves to reestablish itself as a major power within the Orion Arm.