The Terran Dominion, sometimes simply known as the Dominion, was created shortly after the fall of the Confederacy at the height of the war between the terrans, the zerg and the protoss from the Sons of Korhal and many other terran factions. Korhal IV is the throne world of the Dominion.
The roots of the Terran Dominion spring from the Rebellion of Korhal, a "terrorist" faction which emerged when the Terran Confederacy put down a rebellion against them on the world of Korhal. The Confederate attempts to weaken the Rebellion backfired when they slew its first leader; Arcturus Mengsk became its new leader and was even more effective. When Mengsk forged an alliance with the Umojan Protectorate, the Confederates destroyed the world of Korhal using nuclear weaponry. Mengsk renamed the Rebellion the Sons of Korhal. The rebel movement fought against the Confederacy, allying themselves with former Confederacy Alpha Squadron leader General Edmund Duke and eventually destroying it using psionic devices to lure the zerg to the Confederate homeworld of Tarsonis. This action alienated two good-hearted Sons of Korhal officers, Sarah Kerrigan and Jim Raynor. The former was abandoned on Tarsonis and infested by the zerg while the latter defected with a rebel movement. After the death of Arcturus Mengsk at the hands of Sarah Kerrigan the Queen of Blades Crown Prince Valerian Mengsk rules the Terran Dominion on a Redeeming side of good.