Complex sentence: Antiga Prime was a colony of the Terran Confederacy during the events of the first game; however, the colonists had become disillusioned by the Confederacy, and with help from the Sons of Korhal initiated a rebellion.
Split into simpler sentences: Antiga Prime was a colony of the Terran Confederacy during the events of the first game. However, the colonists had become disillusioned by the Confederacy, and with help from the Sons of Korhal initiated a rebellion.