The Selelvians posessed a mental manipulation/control ability that the Selelvians referred to as the "Knack". The Selelvians were a member of the United Federation of Planets until evidence that Selelvian delegates were using the "Knack" to manipulate Federation council procedings was uncovered in 2376. (NF novel: Stone and Anvil)
The conflict start after an incident aboard the Federation starship USS Trident after the Selelvian Gleau was killed on that same starship. The Selelvian government demanded that Janos, the Excalibur crewman who had been accused for the murder, be turned over to them. As they wanted to uncover why the "Knack" had failed against Ensign Janos. (NF novel: Stone and Anvil)
Elizabeth Shelby, as commander of the USS Trident, was instrumental, together with the USS Excalibur and the USS Enterprise were key to the revelation of Selelvian telepathic manipulation of the Federation Council. This revelation lead to the Federation revoking Selelvia's membership. In retaliation, the Selelvians allied themselves with the Tholian Assembly and a short war between the Federation and the Selelvians was the result. (NF novels: Stone and Anvil, After the Fall; NF short story: "Pain Management")
During the war, a shuttle transporting Soleta and Captain Elizabeth Shelby was attacked by Orions and forced down on a barren planetoid. In order to protect Shelby's life, Soleta administered a Vulcan nerve pinch to Shelby, and attacked the Orions single-handedly. Soleta was severly injured, and during her subsequent medical treatment, her half-Romulan heritage was finally discovered. (NF short story: "Pain Management")
Selelvain renegades continued to plague the area around the New Thallonian Protectorate in 2379.