Originally made as a ploy of Wirlokk, the CIUS was mainly made up of Omega's Centauri Forces and Rendros droids. Under Omega it flourished, and immediately after its creation Geonosis joined. During the events of 4th Sith, Wirlokk made his power grab and began a war between the Fourth Republic and the CIUS. After two years of fighting, a daring attack by the Republic resulted in the CIUS being forced to sign a peace treaty, and the nations ended their conflict. After Zaroc the Lower Viceroy Yiff ascended to Supreme Viceroy.