2553

2553 was a year in the Military Calendar.

Background
2553 was one of the bloodiest years in the Human-Covenant War, as well as the last.

It saw the Human and Separatist victory of the Great War over the Covenant Loyalists. As well as the full destruction of Gravemind-lead Flood forces, and his death. It is unknown if the Loyalists have been disbanded or were completely destroyed at the Battle of Installation 00.

Second Battle of Earth
At the beginning of the year, Covenant Loyalist forces assaulted the Human city of Cleveland, Ohio in the United States on Earth. The Loyalists were looking for the Key of Osanalan, a mysterious Forerunner device related to the Halo Installations.

Later during the Second Battle of Earth, a battle at Pawas in Afghanistan took place. There, UNSC Marine Corps forces battled Loyalist forces for control of a Satellite installation. Numerous Marines of the 2nd ODST Battalion targeted the Forerunner Dreadnought entering Earth's atmosphere. Onboard was one of the last SPARTAN-II Commandos, Master Chief Petty Officer John-117.

Battle for Kenya
During the Battle for Earth, the Crow's Nest was an Underground Facility used by the UNSC Defense Force to coordinate local Army, Navy, and Marine forces.

Shortly after John-117's arrival in Kenya, Loyalist forces attacked the facility in force, supported by a CCS-class Battlecruiser orbiting above the savannah.

SPARTAN-117, SgtMaj Avery Johnson, the Arbiter, GySgt Pete Stacker, and GySgt Reynolds then organized a defense of the base. First, they attacked infantry in a large roadway containing numerous supply trucks and armament. Then, they engaged one of the bases hangars in control by Jiralhanae forces, with support by Type-52 "Phantom" Troop Carriers. When they took control of that hangar, it allowed Marines to escape from the base.

Soon after the short skirmishes, they detonated a large bomb in the Operations Center, effectively destroying the base and all enemy forces within it.

United Nations Space Command

 * Commander Miranda Keyes
 * Sergeant Major Avery Johnson

Covenant Loyalists

 * High Prophet of Truth

Forerunners

 * 343 Guilty Spark

Flood

 * Gravemind

Battles

 * Battle of Mare Erythraeum
 * Second Battle of Earth
 * Battle of Cleveland
 * Battle of Pawas
 * Battle of the Crow's Nest
 * Battle of Voi
 * Second Battle of Mombasa
 * Battle of Installation 00
 * Second Battle of High Charity