Morith was a Klingon military officer during the late 2280s.
In 2286, Morith took part in a complex plot to fool Captain James T. Kirk. Morith, Kalrind, and numerous other Klingons ingested a drug that allowed them to act more Human. These Klingons then told Kirk that he had accidentally been transported into the future, where a new breed of Klingon had taken control of the Empire and made peace with the Federation.
Morith then convinced Kirk that it was necessary for the new Klingons at the base and Kirk to travel back in time in order to initiate the peace between the Empire and the Federation. Morith's actions slowly made Kirk suspicious and once they had "travelled through time," Kirk beamed back to the USS Enterprise-A. Once he had his suspicions confirmed, Kirk confronted Morith, and the latter admitted that he and others had taken drugs in order to fool Kirk, and surreptitiously get a Klingon invasion fleet to Earth under false flag of truce. (TOS novel: Timetrap)