Breen Confederacy

The Breen Confederacy is the Breen state.

In 2375, under the leadership of Thot Gor, the Breen Confederacy allowed itself to be annexed by the Dominion, joining the Dominion War during that conflict's closing months. Forces from the Breen Confederacy launched an attack upon Earth, the capital planet of the United Federation of Planets, destroying much of Starfleet Headquarters, San Francisco, and other cities on the surface, killing thousands. ("The Changing Face of Evil" [DS9], "Eleven Hours Out" [Tales of the Dominion War].)

While Breen forces initiall led to several Dominion victories due to their energy-dampening weapon, the weapon was later countered, and the Breen later surrendered along with the rest of the Dominion in orbit of Cardassia Prime. The subsequent peace treaty re-established the Breen Confederacy and the Cardassian Union as independent states. ("What You Leave Behind" [DS9].)

The Breen Confederacy remained an object of concern for many in the Federation following the war. (Vulcan's Soul, Avatar.)