A short war between the Federation and the Klingon Empire that grew out of the Klingon invasion of Cardassia and ended when the two powers renewed their alliance against the Dominion.
The Federation-Klingon War of 2372-2373 runs through the fourth and fifth seasons of Deep Space Nine. In The Way of the Warrior the Federation condemns the Klingon attack on Cardassia, Chancellor Gowron withdraws from the Khitomer Accords, and a Klingon fleet assaults Deep Space 9. A year of raids and tension follows.
Open war comes at the end of Broken Link, when Gowron demands that the Federation leave the Archanis sector. Nor the Battle to the Strong shows the fighting on the ground at Ajilon Prime, through the eyes of Jake Sisko.
In Apocalypse Rising a team led by Benjamin Sisko exposes a Changeling posing as General Martok, which opens the way to a ceasefire. The quarrel finally ends in By Inferno's Light, when Cardassia joins the Dominion and Gowron signs the accords again so that Klingon forces can help defend the station.