The Saltah'na were an ancient species in the Gamma Quadrant who were destroyed by a power struggle among their ruling members. The Saltah'na preserved their essence in a series of energy spheres. The spheres had the ability to merge with the conscious personality of certain humanoid species, causing the personalities of the most prominent members of the original power struggle to emerge and eventually supplant the personalities of the individual who came into contact with the sphere. This had the additional effect of causing that individual, and those around him, to re-enact the disastrous events that destroyed the Saltah'na.
In 2369 the Klingon starship IKS Toh'Kaht traveled to the Gamma Quadrant and encountered the spheres. As a result of the ensuing power struggle the ship barely managed to return to the Alpha Quadrant before it was destroyed. Shortly before its destruction the first officer, Hon'Tihl beamed aboard Deep Space 9, transferring the spheres to the station in the process. Shortly after the crew of that station began to re-enact the Saltah'na struggle all over again before finally managing to undo the influence of the spheres. (DS9: "Dramatis Personae")