In the Star Trek universe, the Dominion is a technologically advanced planetary alliance in the Gamma Quadrant that is composed of hundreds of oppressed races. It was conceived by the creators to serve as a contrast to the United Federation of Planets, with its ideologies of domination and extortion.
The first interaction with the Dominion takes place in Star Trek: Deep Space Nine season 2, episode 26, “The Jem'Hadar.” It expresses its displeasure, in a series of attacks and threats, about the Alpha Quadrant powers exploring the Gamma Quadrant after the discovery of the Bajoran wormhole, and warns the Federation to stay on its side of the anomaly. This establishes the Dominion’s philosophy from the beginning: it aims to bring “order” to the galaxy by keeping a stranglehold on its subjects.
The Dominion is essentially a coalition of three species, all bound by a unified, aggressive strategy of expansion and suppression: the Founders, who hold the ultimate authority; the Volta, who serve as administrators that recruit others to join the Dominion, and as commanders of the storm troops; and the Jem'Hadar, the military arm that eliminates species and planets that fail to comply to the Dominion’s agenda. The hierarchy is strictly kept in place, and any deviation from it can lead to immediate death.
The Three Primary Races
The Founders
The Founders, also known as the Changelings, are a race of shape-shifters who are responsible for the creation of the Dominion. They have no interest in matters concerning the humanoid populations (or the ‘solids,’ as they call them), who would previously attack them out of fear. This ultimately led to the Founders, who are experts in genetic engineering, to create the slave races for their protection.
Even though they are perceived as infallible gods by their subordinates, whose commands cannot be questioned, the Founders prefer to distance themselves from the administrative affairs of the Dominion. Instead, they depend on the Vorta to take control of the conquered territories and the Jem'Hadar to strong-arm the different planets to become part of the Dominion (and launch all-out invasions if deemed necessary). They are more concerned with those matters that could shape the future centuries from now.
With their strong anti-individualistic values, the Founders prefer to keep to themselves and jointly share power in a collective union called the Great Link. They are governed by a single overarching principle: no Changeling will ever harm another. This principle reflects both their oneness and their primary goal of achieving and ensuring complete protection from outside forces.
The Vorta
The Vorta are clones who serve as administrators, commanders, diplomats, and scientists. They are responsible for managing the economic, military, political and other day-to-day operations of the Dominion. Apart from the rare instances where they get to consult one of their leaders, they are largely left on their own in dealing with the Jem’Hadar soldiers or maintaining the infrastructure and fleet of warships.
While they seem like friendly diplomats on the surface, they are almost fanatical believers who are committed to furthering the Founders’ cause in any way they can. However, the Founders only perceive them as non-essential beings who can easily be replaced if they fail in their mission in any manner or are killed in the line of duty. Each Vorta’s DNA is recorded so that they can be cloned in such cases.
The Jem’Hadar
The Jem’Hadar are made to propagate and mature at a quick pace to ensure virtually unlimited troops who can enforce the will of the Founders. With a “victory is life” mantra, they are considered as one of the most powerful military forces in the galaxy, fighting wars to protect and expand the Dominion. With the ability to cloak themselves from their rivals, the Jem’Hadar deprive themselves of basic necessities to focus their efforts on warfare.
Each group is overseen by the Vorta, who often assert their dominance over them with the use of ketracel-white — a drug that has been developed by the Founders that could cause the Jem’Hadar to have episodes of extreme violence and eventually die.
Other Members of the Dominion
Through military conquest and coercion, the Dominion expanded to include several other subjugated members, including the Karemma, the T-Rogorans and the Yaderan. While the Dominion did not see the need to join forces with other species, it made an exception for the Cardassian Union after establishing a power base in the Alpha Quadrant. Since it required a base of operations, it allowed the Cardassians to have full control over its fleet of operations. It expected to conquer the Cardassians after it had defeated the Federation and achieved its purpose.
This partnership led to the Dominion War, which became the biggest threat to the Alpha Quadrant since the Borg Invasion of 2381. However, since the war was not going in its favor, the Dominion allied with the Breen Confederacy, also from the Alpha Quadrant. The growing relations between the Dominion and the Breen led to tensions with the Cardassians, who ultimately joined the opposing party, leading to the defeat of the Dominion.
What Happened to the Dominion After the War?
The Dominion War ended with the Female Changeling’s surrender, in exchange for a cure to a virus spreading within the Great Link. A peace treaty was signed between the major powers of the Alpha Quadrant and the Dominion, and the latter returned to its territory. Although the fate of the Dominion is not entirely revealed in the Star Trek canon, it is assumed that it still remains the higher power in the Gamma Quadrant.