In the early 24th century, the overpopulation has caused the international governing body, known as United Powers League (which was later succeeded by United Earth Directorate), to cast out certain members of the human race, such as criminals, the cybernetically enhanced, and genetic mutants, to colonize the far reaches of the galaxy. An attempt to colonize a nearby solar system goes wrong, resulting in humanity's arrival in the Koprulu Sector. In the distant Koprulu Sector of the galaxy, the exiles form several governments, but quickly fall into conflict with each other. One government, the Confederacy of Man, now incorporates as the most powerful faction, but its oppressive nature and brutal methods of suppressing dissidents stir up major rebel opposition in the form of a terrorist group called the Sons of Korhal. In December 2499, an alien race possessing advanced technology and psionic power, the Protoss, makes first contact with humanity by destroying a Confederate colony world without any early warning. Soon after this, the Terrans discover that a second alien race, the insectoid Zerg, has been stealthily infesting the surface of several of the Terran colonies, and that the Protoss are destroying the planets to prevent the Zerg from spreading. With the Confederacy threatened by two alien races and internal rebellion, it begins to collapse.
