The Corporation wars is an event spanning the Unreal series.
The Corporation Wars is a three-way series of wars carried on between Liandri Mining Corporation, Axon Research Corporation and Izanagi Corporation. The starting year of this war is unclear, but it's been known for spanning over a long time, and even taking place during the Tournaments.
Unreal II: The Awakening Edit
Unreal Tournament 2003 & 2004 Edit
The map AS-Glacier covers an event of the war in 2260, where an Axon team raided an Izanagi facility and stole an Ion Plasma Tank, destroying the Izanagi base and escaping with the tank in the process.
Bonus Pack 2 Edit
Although the canonical status of this pack is unknown, the map AS-BP2-Jumpship relates to an episode of this war between Liandri and Izanagi, where Izanagi spies infiltrated the prototype Liandri Jumpship, activated its engines, and made a successful jump to Izanagi space. The year of this event is unknown.
The event itself is a foreshadowing of the Ronin team's Izanagi ship hijacking in UT3, meaning that at least the capture of the jumpship indeed happened.
Unreal Tournament III Edit
Malcolm's description in the official web says that "Tournament stars and team captains are often recruited by the major corporations to serve as consultants for training or leading their paramilitary security forces".