Halo Alpha
Halo Alpha

The Interplanetary War was a large war between the United Nations, Koslovics, Friedens, and a number of other National governments.[1]


As overpopulation and unrest mounted on Earth, a number of new political movements were formed, including the Koslovics and the Jovian Frieden movement (the latter of which attacked the United Nations Colonial advisers on Io, one of the moons of Jupiter) and UN-sponsored military forces began a pattern of massive buildups which culminated with the Interplanetary War. After a successful Marine attack on Mars, recruitment drives and propaganda tactics strongly bolstered UNSC forces.[1]   


Main articles: Frieden and Koslovics

The United Nations[]

Homeworld: Earth
Military Forces: Unknown. Likely hundreds of thousands if not millions of soldiers and Marines.

The Koslovics[]

Homeworld: Earth
Military Forces: Likely hundreds of thousands or millions of followers and volunteers.

The Frieden[]

Homeworld: The Jovian Moons
Military Forces: Unknown. Likely hundreds of thousands or millions of followers or volunteers.


Homeworld: The Jovian Moons, and possibly Delambre.
Military Forces: Unknown. Likely thousands of followers or volunteers.


The following are the key events that led to the Interplanetary War and events that occurred during the course of the Interplanetary War. There were probably additional conflicts all around the Solar System and on Earth, but for the most part, the conflict was centered around the UN, Koslovics and Frieden forces.


Jovian Moons campaign[1]

Secessionist forces, mostly Frieden rebels, attack UN Colonial Advisors on Jupiter's moon Io. This leads to several months of fierce fighting between UN forces and Frieden rebels on the moons. Though it was not the first engagement, it was one of the bloodiest, leading other Earth Governments to fight proxy wars off-planet and across the Sol System. This later led to the Rainforest Wars.


The Rainforest Wars[1]

Heavy armed conflict between UN, Koslovic, and Frieden, erupts in the tropical rain forest area of South America. The clashes resulted from ideological differences and the wish to control important areas of Earth. As the conflict raged, this sparked even more fighting on moons and other planets in the Sol system.

Battle of Delambre

Friedenists and Neo-Friedenists clash over internal differences on Luna.


Argyre Planitia Campaign[1]

The UN launches various lightning strikes against Koslovic forces in the Argyre Planitia on Mars. This was the first deployment of extraterrestrial Marines by the UN. This would later be used as a military doctrine in all situations off-planet, and would mark the start of the UNSC.


Recruitment drives and propaganda tactics strongly bolster UN forces. UN forces defeat Koslovic and Frieden forces on Earth, and then begin a systematic and dedicated drive to crush their remnants on the various planets they hold throughout the system. At the conclusion, Frieden and Koslovic forces are defeated, in the face of a massive, unified, inspired, and very powerful UN military, now known as the United Nations Space Command.


2170 marks the end of the Interplanetary War with the Callisto Treaty, with the Koslovics and Frieden commanders surrendering to the UNSC.[1] 2170 also saw the formation of the Unified Earth Government in the wake of the conflicts of the 2160s. After the conflict, the UNSC were forced to deal with a less obvious but equally serious threat: overpopulation and a massive military that has no enemy to fight. In the post-war period, there were massive population surges and the overpopulation that, coupled with the destruction and famine bred by the Rainforest Wars, threatened to destabilize the economy.

See also[]