In the Star Trek universe, the Dominion is a ruthless and militaristic Gamma Quadrant state consisting of many different races. The Dominion waged war on the United Federation of Planets and its allies in the late 24th century, acting as an antagonist in the TV show Star Trek: Deep Space Nine.
The Dominion was created over nine-thousand years prior to the events of Star Trek: Deep Space Nine, when the persecuted Changelings (a non-humanoid race of shape-shifters) decided that the only way they could defend themselves against the "solids" (as the Changelings call all other races) was by bringing them under their control. Unwilling, or unable, to trust existing "solids," the Changelings genetically engineered new slave races to be their diplomats and soldiers. In so doing, they became known as the Founders to their new slaves.
Their main fighting force are shock troops known as the Jem'Hadar, fanatical super-soldiers who require no sleep or food and whose loyalty is ensured by a genetically pre-programmed addiction to the drug ketracel white, which only the Founders can provide, as well as an innate genetic veneration of Changelings and a heavy system of indoctrination that prepares Jem'Hadar for lives of devoted service in the interests of the Changelings. The Vorta serve as the Founders' cloned intermediaries acting as Dominion administrators, diplomats, command staff, and scientists. Vorta are known for their duplicity and Machiavellian treachery, though they maintain ultimate service to the Dominion. It has been said that the tree-dwelling ancestors of the Vorta once protected a changeling, and they were elevated to their new role in gratitude. Both the Vorta and the Jem'Hadar have been conditioned to see the Founders as living gods.
Other races in the Dominion include the Hunters, the navigators and trackers of the Dominion (a Hunter was supposed to appear on a Dominion ship in the episode "Broken Link" but the idea was dropped so as not to confuse new viewers ), and their prey, the Tosk (which are rumored to come from the same 'root' species as the Jem'Hadar). These races appeared in the Deep Space Nine Season One episode "Captive Pursuit". Other Gamma Quadrant races fled their home worlds after being conquered by the Dominion. The Skrreea, for example, flooded Deep Space Nine with refugees after fleeing from their conquered world in the Season Two episode "Sanctuary." Still other races subject to the Dominion provide logistical support: one race manufactures torpedoes for Jem'Hadar ships, another race builds those ships. Only the Vorta and Jem'Hadar have direct contact with the Founders.
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