Cyberon War

The Cyber-War, also called the Cyberon War, was the protracted conflict between the Cyberons and the Earth Alliance.

Nature
Once, while aboard a Cyberon vessel, Captain Harcourt Ross noted that one of the reasons the Cyber-War was taking long to win was because the Cyberons could convert both living and dead organisms. (PROSE: Flight of the Cyberons) A few centuries later, with the war long won by humanity, it was sarcastically called an expensive "war on drugs" by one time-traveller. (PROSE: Barnyard of the Cyberons)

History
The War was waged for around a century. Eventually, the Cyberons began developing advanced, portable nanite-based Conversion Engines (PROSE: Flight of the Cyberons, Cyber-Hunt) which proved their undoing when a man on the Earth side managed to reprogram the Cyberons' own nanites to seek out and destroy Cyberons instead of making more of them. (PROSE: Cyber-Hunt, The Blue Scream of Death) Depending on accounts, these events occurred either around 2777 (PROSE: Cyber-Hunt) or around 3909. (PROSE: Flight of the Cyberons)

Behind the scenes
The Cyber-War against the Cyberons first appeared in the Audio Adventures in Time & Space story Cyber-Hunt, in which a mysterious "Fred" (implicitly an amnesiac version of Nicholas Briggs' Doctor) allies with a team of human soldiers on Carson's Planet and discovers a secret Cyberon facility developing nanite conversion methods, which the Wanderer tampers with so that the nanites attack Cyberons. Cyber-Hunt was adapted from an unproduced BBV Productions film called Cyber-War, which was at one point an adaptation of Sword of Orion and at another point was planned to feature Cybermen and Ice Warriors in conflict. (REF: Downtime – The Lost Years of Doctor Who) It was later novelised under the same name by Callum Phillpott; this new version of the narrative is the only one covered by this Wiki, as it introduced DWU elements into the plot, such as Aurichall. Nevertheless, it postdated Flight of the Cyberons, which thus stands as the first use of the Cyberon War in a valid DWU story.

Arcbeatle Press's Cyberon and the NiT&S Cybergeddon both place the end of the Cyberon War around 3009, suggesting the brunt of it took place in the 30th century. However, the Cyber-Hunt novelisation seems to operate with an earlier time-scale in mind, placing the end of the War in 2777 and thus presumably placing the War in the 27th century and 28th century.