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This article is about the conflict of 2372/73. You may be looking for the Betreka Nebula Incident of 2328-46.
For other uses, see Federation-Klingon War.

The Klingon-Cardassian War was a one-year conflict (2372-2373) between the Klingon Empire and the Cardassian Union. The Klingons were manipulated by the Founders into launching an unprovoked attack on the Cardassians, which left the Union devastated and paved the way for its alliance with the Dominion. This conflict proved to be one of the greatest coups of Changeling infiltration in the Alpha and Beta Quadrants. (DS9 episode & novelization: The Way of the Warrior; DS9 episodes: "Return to Grace", "Rules of Engagement", "For the Cause")

Cardassian revolution and Klingon paranoia

Following the destruction of the Obsidian Order and the threat of Changeling infiltrators, the Cardassians sealed their borders. Not long afterwards, the Cardassian dissident movement mounted a popular uprising, overthrowing the Cardassian Central Command's military dictatorship and restoring power to the civilian Detapa Council.

On Qo'noS, Klingon Chancellor Gowron and the High Council saw it as unlikely that the Cardassian civilian population and the known dissident movement had overthrown the Central Command by themselves and that it had likely been instigated by the Dominion Founders impersonating members of the Detapa Council. The Klingons paranoia and fear of the Dominion infiltrators was amplified by a changeling impersonating General Martok, calling for a massive invasion of Cardassian space to end the "Changeling threat". Many Klingons, who had grown restless after decades of peace, rallied around him not knowing that Martok himself had been replaced by a Changeling, whose mission was to weaken the Dominion's enemies.

The invasion was to involve a third of the Klingon Empire's military forces, with over a hundred ships in the first wave alone. The plan was to mount a lightning thrust into the heart of Cardassian territory and conquer Cardassia Prime. All governmental officials would be executed, and an imperial overseer installed to put down any further resistance. The advance task force of over fifty warships, led by Martok aboard the IKS Negh'Var, was dispatched to Federation starbase Deep Space 9 under the guise of defending the station against a Dominion incursion. (DS9 episode & novelization: The Way of the Warrior)

Starfleet's response

However, the sheer number of ships and troops, combined with several incidents on and near DS9, caused station commander Captain Benjamin Sisko to become suspicious enough that he sent for Lieutenant Commander Worf (late of the USS Enterprise-D) to come and investigate the Klingon presence. Worf eventually uncovered the true purpose of the taskforce and relayed this information to Sisko, who in turn relayed it to Starfleet Command and the Federation Council. The Council refused to support the invasion, going so far as to condemn it altogether. In response, Gowron withdrew the Klingon Empire from the Khitomer Accords, expelled all Federation citizens from the Empire and recalled all his ambassadors. (DS9 episode & novelization: The Way of the Warrior)

Escape of the Detapa Council

Sisko, realizing that it was in fact possible that the popular uprising could have succeeded in bringing down Central Command, was able to get word to the Cardassians that the Klingons were coming. Despite this, the outlying colonies of the Union were overrun almost immediately, though the mobilization of the Cardassian fleet did slow them down. Eventually, though, the lines broke and the Klingons came very close to Cardassia Prime.

Skrain Dukat, who had become the Chief Military Advisor to the Detapa Council, was contacted by Sisko, who promised the council members safe haven aboard DS9, provided they could rendezvous with the USS Defiant. While the CDS Prakesh (the ship boarded by the council members for the trip) was able to reach the coordinates, it was attacked and pursued by the Klingons, and by the time the Defiant arrived, it was on the verge of destruction. The council members were evacuated to the Defiant, which promptly made a beeline back to DS9 with two Klingon vessels (which had been attacking the Prakesh) in pursuit. When the Defiant finally returned to DS9, a large portion of the Klingon fleet attacked the station, leading to a long firefight that only ended when a Starfleet task force under Admiral Hastur was able to beat the Klingon reinforcements to DS9. (DS9 episode & novelization: The Way of the Warrior)

Klingon starships attacking Cardassian starships.


By Stardate 49066.5 (2372), the Klingons had succeeded in conquering a number of outer Cardassian planets, but the Cardassian Guard managed to stall their advance. To avoid challenge or assassination, Chancellor Gowron declared victory and began preying on surrounding systems. He eventually started a low-intensity war with the Federation over long-disputed systems in the Archanis sector, as well as attacking several targets on the border with the Romulan Star Empire. Meanwhile, the Founders, while punishing Odo for killing another changeling in self-defense in 2371, planted disinformation implicating Gowron as a changeling infiltrator. (DS9 episodes: "Hippocratic Oath", "Broken Link")

Gul Dukat, who had been sacked from his advisory position over fathering a half-Bajoran child and now commanded the freighter CDS Groumall, took Kira Nerys aboard with him for a trip to Korma, where she was to deliver Bajoran intelligence on the Klingons. They were attacked by a B'Rel-class bird-of-prey, which had destroyed the Korma colony. Dukat fired on it but inflicted no appreciable damage, and the bird-of-prey left to seek a more interesting target. Dukat and Kira jury-rigged a system-5 disruptor from the colony's anti-ship defenses to Groumall and pursued the Klingons, successfully capturing the ship. Dukat reported his success to the Detapa Council, but upon learning that his civilian superiors wished to use the ship as leverage in peace negotiations, went rogue to begin his own guerrilla war with the Klingons. (DS9 episode: "Return to Grace")

With Dukat's help, in 2373 Worf, Sisko, and Odo infiltrated the induction ceremony for the Order of the Bat'leth, intending to unmask Gowron as a changeling infiltrator. Worf challenged Gowron for the chancellorship, but before either could gain the advantage, they instead discovered they had been duped and Martok was in fact the infiltrator. The changeling died in a hail of disruptor fire, but peace was not restored and the wars continued, with the Klingons mounting an attack on Federation member Ajilon Prime later in the year. (DS9 episodes: "Apocalypse Rising", "Nor the Battle to the Strong")

A sudden conclusion

Behind the scenes, Gul Dukat approached the Dominion in secret, offering them the Cardassian Union as a foothold in the Alpha Quadrant if they would make him its dictator. On Stardate 50564.2 (2373) the Dominion invaded, a changeling who had replaced Julian Bashir sabotaging the Federation's attempt to force the Bajoran wormhole closed. The Klingons were caught off-guard, and in short order the Jem'Hadar drove their occupation forces in Cardassian space into full retreat. On Stardate 50953.4, they then advanced into the disputed worlds in the Demilitarized Zone and wiped out the Maquis in three days. On Cardassia itself, the Dominion overthrew the Detapa Council and installed Dukat to rule on their behalf. (DS9 episodes: "In Purgatory's Shadow", "By Inferno's Light"; VOY episode: "Hunters")

Benjamin Sisko talked Gowron into signing the Khitomer Accords. Deep Space 9's sensors detected a Dominion invasion fleet inbound, and several dozen Starfleet, Klingon Defense Force, and Romulan Imperial Fleet ships gathered at Deep Space 9 to defend the critical station. However, this was a feint: the signals were faked by the Bashir changeling, who in fact planned to use a trilithium warhead to detonate the B'hava'el sun. He was discovered, and killed in the explosion of USS Yukon after the USS Defiant tractored him away from the star. (DS9 episodes: "In Purgatory's Shadow", "By Inferno's Light")


The Dominion continued to send convoys of warships into Cardassian space weekly for several months. Benjamin Sisko, knowing war was imminent, proposed to Starfleet Command that the allies build a field of self-replicating mines over the Bajoran terminus of the wormhole before the Dominion's numerical advantage became insurmountable. This led directly to the start of the Dominion War. (DS9 episode: "Call to Arms")

Associated events

External link