Cyber-Wars

The Cyber-Wars was a galactic conflict in which an alliance made a concerted effort to wipe out the Cybermen.

Origins and the Conflict
The conflict began in 2526 (TV: Earthshock) and lasted for 1,000 years. (TV: Nightmare in Silver) A force of time-travelling Cybermen from the end of the conflict attempted to prevent the war. They tried to destroy the Earth, first with a Cyber-bomb and then by crashing a human freighter into the Earth to prevent the alliance who planned to fight them from forming. Both of these attempts were stopped by the Fifth Doctor. (TV: Earthshock)

It was during this conflict that the glittergun was developed. Gold was a major weakness of the Cybermen. The gun could fire gold dust at them. (TV: Revenge of the Cybermen) The war ended when the humans destroyed Tiberian spiral galaxy. All the Cybermen were thought to have been killed. (TV: Nightmare in Silver, Tomb of the Cybermen)

Aftermath and Later Events
The wars resulted in near-complete destruction of the Cyber race. Remnant groups of Cybermen fled across the galaxy. One remnant group attempted to retaliate by destroying Voga, the planet of gold but were destroyed when the Fourth Doctor instructed the Vogans to fire their rocket at the Cyber-ship. (TV: Revenge of the Cybermen)

The Cybermen were thought to be extinct for centuries after the war. Some dead Cyber-suits, including some Cybermen originating from a parallel universe, were thought to be all that remained of their race. However, three million Cybermen had retreated to a planet where they could be repaired and when Hedgewick's World of Wonders was built, the Cybermen remained hidden in their tombs. Their Cybermites eventually worked to reawaken them but their reviving forces were destroyed when Emperor Ludens Nimrod Kendrick Cord Longstaff XLI activated a bomb which destroyed the planet. However, one Cybermite remained, drifting in space. (TV: Nightmare in Silver)