The Racnoss Wars were a conflict between the Time Lords' Fledgling Empires and the Empire of the Racnoss. The Fifth Doctor described the Racnoss Wars as "a long and bloody affair". (AUDIO: Empire of the Racnoss)
The Racnoss attacked a Fledgling Empire outpost on Trakkiney during the wars. (PROSE: The Labyrinthine Web)
The Fifth Doctor's TARDIS was brought into the conflict after a conscientious objector circuit was activated. (AUDIO: Empire of the Racnoss)
Almost all of the Racnoss were wiped out in the conflict, apart from one Webstar which escaped to the site where Earth would be formed. (TV: The Runaway Bride) Rassilon boasted to Pandoric that he had "wiped out the voracious Racnoss." (PROSE: Pandoric's Box)