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Previous battle: Rain Forest Wars
Concurrent battle: Interplanetary War
Next battle: Unknown
Argyre Planitia Campaign
Conflict: Interplanetary War
Date: December 2163
Place: Argyre Planitia, Mars
Outcome: Marks first use of Marines off Earth, and the beginnings of the United Nations Space Command. Decisive UN victory.
Belligerents
United Nations	Koslovics	Frieden
Commanders
HIGHCOM UN Council	Vladimir Koslov	Unified German Republic Corporations
Strength
UN Fleet Marines
Casualties

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.

Timeline

December 2163

In a conflict that stemmed from The Rain Forest Wars, the three primary Earth factions clash again, this time on Mars^[1]. A series of lightning strikes against Koslovic forces near the Argyre Planitia marks the first extra-terrestrial 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.

Sources

1. ↑ http://www.xbox.com/en-US/games/h/halo/storyline.htm