GalSec

Galsec was a human colony, descended from a colony ship sent out by the Earth around the time of the Expansion. During the following 10,000 years they established an Empire with bases across the Galaxy. (DW: The Sontaran Experiment) A number of pre-existing colonies were taken over, and prejudice existed among GalSec colonists against the original colonies ("indig's"). (BFA: Wirrn Dawn)

At some point the Sontarans lured a group of GalSec soldiers to Earth with a fake distress signal in order to test their fighting capabilities. (DW: The Sontaran Experiment)

GalSec would spend a number of years at war with the Wirrn. (BFA: Wirrn Dawn)