USC ArmyThe USC Army was created when the Tractus Bailicae was signed. They have since become the main fighting force of the USC on the ground. Often they are put onto a planet after the USC Marines establish a beach-head. They are trained in ground warfare along with air warfare. They are like all of the USC Military equipped with the most reliable and effective technology available.
History of the USC Army
The USC Army's first major engagement was in the Asian-Christian War. They fought valiantly and become the face of the USC Military. At that time they were still heavily divided by their nationality. Often the military units would fight under the flag of the former nation they were from. One of the famous examples was the American regiment which charged the Asian lines with the American flag leading the charge.
After the war the national flag of the USC was adopted but units still often carried their national flags as battle flags. The USC Army adopted the practice of carrying the flags into battle officially on August 13, 2100 but by that time the practice was already wide-spread. The time of peace that they enjoyed between the acquisition of the entire world and the great rebellion 'dulled the swords' of the USC Army as it adopted an extended peace time role. Also during this time the USC Army incorporated the USC Air Force.
Because of this 'dulling' they suffered heavy casualties during the Great Rebellion as they were met by a fighting force of nearly equal determination and that fought in a guerrilla style most of the time. They did however win many of the battles but they were almost always pyrrhic. The heavy losses often degraded the morale of the USC Army but in the end they did eventually come out on top.
Human-Covenant WarThe Human-Covenant War was perhaps the most costly war ever. The USC Army was although veteran fighters because of the rebellion but nothing prepared them for this war. They were killed in droves as they were smoldered by the plasma bolts of frenzied aliens. They became known often as the 'Kamikazes' as they were sent in often as cannon foder as the situation became so desperate that often children older then 13 were conscripted into the Army. They were almost always defeated except when a Paladin was present in which case they would often be inspired to nearly willing to become 'Kamikazes' and charge in suicidal waves against the Covenant. They did eventually beat the Covenant but only after the Sangheili and Mgalekgolo allied with the USC.
Post Human-Covenant War
The USC Army accepted the Sangheili and Mgalekgolo into their ranks almost immediately after the allied with the humans. This process of integration helped ease the transition from a Human-only peoples to an integrated society.
During the final destruction of the Covenant on High Charity they sent in a squad of Paladins with at least a battalion of Mgalekgolo that volunteered for the fight.
Rebellion of New Quebec
The USC Army played a heavy role in the capturing of New Quebec as they were the ones who almost soley took the entire planet due to their new weaponry and vast numbers.