Breen Confederacy
The Breen are a spacefaring humanoid species native to the planet Breen in the Alpha Quadrant. Notoriously reclusive and warlike, the Breen are a formidable power in their region of the galaxy. They almost always wear refrigeration suits that entirely conceal their bodies.
Government
If the Breen have an organized political body, they keep it as secret as most other aspects of their lives and culture. The Ferengi have sent representatives to Breen, but what, if anything, they learned about Breen politics or mercantilism they are keeping to themselves. Starfleet Intelligence believes they learned nothing at all, despite Grand Nagus Zek's implications that he knows the Breen.
In late 2375, the Breen Confederacy entered the Dominion War by signing an alliance with the Dominion. According to the terms of the alliance, the Breen Confederacy received several planets from the Cardassian Union as compensation for joining the war. The Breen would also be given control of the Romulan Star Empire in the post-war galaxy. The Confederacy proved very influential in its first weeks of fighting, thanks to their previously unknown energy-dampening weapon, in addition to their conventional forces. However, the Allies were able to capture an example of the Breen weapon, allowing them to develop countermeasures. Ultimately, the Dominion and the Breen Confederacy were defeated at the Battle of Cardassia. While several Breen did attend the signing ceremony, the Breen Confederacy was not mentioned in the treaty document itself, though they were subject to the provisions within the treaty restoring territorial boundaries to their pre-war status.
Breen raiders outside of their own space are common. Rather than killing the people they attack, they stun them and then sell them into slavery or impress them as slaves themselves. Very few people make it out of Breen slave camps, and the punishment for running is always death.
Physiology
Breen are humanoid, sharing the same average height and build as humans-presumably. Only a very few have ever been seen outside of their encounter suits: sealed, refrigerated suits of armor designed to keep them comfortable in adverse conditions-any temperature not below freezing. Their reputation as cold-blooded and heartless may be partially true, they have no blood at all (hot or cold) and thus no need for a central circulatory organ or heart. Xenologists have thus speculated that they might be silicon-based lifeforms, but there is no evidence to support this theory beyond the known lack of a circulatory system.
Numerous reports describe Breen soldiers taking full hits to the chest and appendages with little to no adverse effect on them. Likewise, they shrug off low stun settings from phasers as if they weren't even hit. Coupled with the near-impregnable helmets they wear, Breen are difficult to incapacitate if the intention is not to kill them. One remarkable feature of Breen physiology is what Betazoids report as a total lack of emotion. Unlike the Ferengi, who have mental defenses against Betazoid psychic abilities, Breen emotions simply don't register at all.
