In 2550 the war against the Covenant had stretched the UNSC military to the limits, none more so than the UNSC Marine Corps infantry and special operations units. As such the UNSC need fresh troops to bolster nil strength ground units. The UNSC High Command decided to conscript all able body males within the colonies, due to this decision within a handful of weeks there was such an excess of conscripts (after bolstering of the frontline units) that High Command decided to form these excess units into independent infantry battalions. One such battalion was the 226th Infantry Battalion Excalibur, an special operations Battalion of former marines that were recalled into service to be used in deep penetration operation behind the enemy lines.