The Dominion

The Dominion is a major galactic political and military power in the Gamma Quadrant. It was founded somewhere between ten to two thousand years ago by the Changelings, a highly evolved species of shapeshifters.
The Dominion was founded upon xenophobic fear. The Founders once belonged to an ancient race of peaceful explorers who found nothing but fear and hatred in their journeys. Hunted over the galaxy they retreated to a remote planet in the Omarion Nebula. There they formed the Great Link, where they exist in a collective environment, and established the Dominion to exact their own kind of rule and discipline, thus adopting the title of "the Founders". The slaughter of their species convinced them that only through absolute control over every part of the Universe will they live in peace. In time their government's rule and influence extended across the entire Gamma Quadrant.
Through genetically created soldiers called Jem'Hadar, their law and mandates are enforced with extremely efficiency and brutality, while daily duties of administration are relegated to the Vorta, a race genetically altered to serve the needs of the Founders. Their explorer roots did not vanish, so the Changelings sent out hundreds of infants to serve as their eyes and ears. It was expected these Changelings would one day return to the Great Link and input new knowledge into the society. The Dominion also trades with other species through the race of Karemma, who are known as the Dominion's traders. Most member worlds of the Dominion exist with almost full autonomy as long as they bide by the rules set down by the Changelings. The fear of massive Jem'Hadar reprisals is enough to keep most planets in line.
Because of the Dominion's size and influence they are able to obtain many diverse and sophisticated technological systems, like the advanced virtual display interface, sophisticated ion propulsion system, phased polaron beam weapons, shield grids that ensure negative tractor locks, transporters that can beam subjects through shields and across distances of over three light years, anti-proton scans to detect cloaked ships, portable personalised cloaking devices carried by Jem'Hadar troops...