The Argyre Planitia Campaign was a military campaign undertaken by UN forces against human rebel forces on the planet Mars. The Argyre Planitia Campaign marked the beginnings of the UN Space Command (UNSC), and the dedicated usage of large forces of Marines in ground attacks. Predecessors to the Orbital Drop Shock Troopers are known to have engaged in this conflict.
In a conflict that stemmed from The Rain Forest Wars, the three primary Earth factions clash again, this time on Mars. A series of lightning strikes against Koslovic forces near the Argyre Planitia marks the first extraterrestrial deployment of Marines. The campaign is an unqualified success. As a result, future military doctrines will favor large contingents of Marines for ground assaults and ship-boarding actions.