The Dominion was a major galactic political power, whose influence is exerted over thousands of planets in the Gamma Quadrant. The Dominion was founded somewhere between 10,000 and 2,000 years ago by the Changelings, a species of shapeshifters who henceforth called themselves the Founders.
Absolute rule of the Dominion remained in the hands of the Founders and their Great Link, whose decisions could not be disputed under any circumstances. However, the Founders were largely content to leave running the day-to-day affairs of the Dominion to the Vorta. The loyalty of the Vorta and the Jem'Hadar are genetically engineered, which in most cases ensured absolute obediance to the Founders. The Founders themselves were rarely seen, even by their servant races, and were treated as gods or myth.
The Dominion was founded on the principle of control, with the intent being to neutralize any potential threat to the Founders by whatever means necessary. In cases involving cooperative species such as the Karemma, the extent of Dominion interference is fairly minimal and restricted to materiel support. However, if the target species is or becomes less cooperative, the Jem'Hadar are dispatched to wipe out any opposition. The fear of massive Jem'Hadar reprisals is enough to keep most planets in line. For a prospective member, at first contact the Dominion may appear helpful, or even benevolent. A typical Dominion strategy is to make concessions in the short term for an advantage in the longer term, which may be centuries in advance.
There are several member species in the Dominion, as the Founders claim to control the destinies of hundreds of species. Their members include: