- Stardate 23859.7: In what is later known as the Khitomer Massacre, the Klingon colony on Khitomer is attacked and destroyed by Romulan forces. Among the casualties is Mogh, whose son Worf survives and is later rescued by the USS Intrepid. (TNG: "Sins of the Father")
- After the Khitomer Massacre, the USS Intrepid pays a visit to Starbase 24 where another survivor, Kahlest, disembarks for medical treatment. She later books a passage to her home in the Klingon Empire. (TNG: "Sins of the Father")
- The new Cardassian ore processing center orbiting Bajor, Terok Nor, nears completion. (DS9: "Wrongs Darker Than Death or Night")
- Several Bajoran women, including Kira Meru and her daughter, Kira Nerys (who travelled back in time from 2374), are brought to Terok Nor to serve as companions to the Cardassian military officers. Meru is chosen as his personal mistress by the new Prefect, Gul Dukat. She remains in this capacity until her death in 2353. (DS9: "Wrongs Darker Than Death or Night")
- The Bajoran Resistance attempts to kill Gul Dukat by planting a bomb in his quarters on Terok Nor. (DS9: "Wrongs Darker Than Death or Night")
- Paul Stubbs begins to research and construct "The Egg" to study the explosion of the neutron star/red giant in Kavis Alpha sector. (TNG: "Evolution")
- Jean-Luc Picard has an affair with Miranda Vigo on Earth. Shortly after they break up, Miranda becomes involved with another man, also in Starfleet, with whom she will have a son named Jason the coming year. (TNG: "Bloodlines")
- At the age of 5, Julian Bashir performs his first surgery, on his teddy bear, Kukalaka. (DS9: "The Quickening")
- Zek wins the Global Tongo Championship, and will do so for the next 27 years. (DS9: "Ferengi Love Songs")
- According to an alternate Jean-Luc Picard of 2366, a war between the Federation and Klingon began in this year. (TNG: "Yesterday's Enterprise")
- A Saint-Émilion produced this year was present in the holographic recreation of Chez Sandrine on board the USS Voyager in 2371, which was shared by Tom Paris and Harry Kim. (VOY: "The Cloud")
- According to the script for "Coming of Age", Jake Kurland and Oliana Mirren are born this year.
- In VOY: "Initiations", Kar claims that the Kazon overthrew the Trabe 26 years ago, which would place the event in this year. However in "Alliances", it was stated to have happened over 30 years ago.