26th Marine Expeditionary Force

The 26th Marine Expeditionary Force is a UNSC Marine Corps formation, which was a part of a Rapid Offensive Picket. This unit was called in to reinforce Marine ground forces near Mount Haven during the Battle of New Jerusalem in the Cygnus system in late 2552, and they suffered tremendous causalities during the battle.

Only one member of this unit is known; the Rookie, who was transferred to a squad led by Gunnery Sergeant Edward Buck shortly after the unit's near-annihilation.