Curzon Dax

Curzon Dax was a Trill that served as an ambassador in the Federation Diplomatic Corps in the 23rd and 24th centuries. Dax was a part of many negotiations that happened between the Federation and the Klingon Empire in the late 23nd and early to mid 24th centuries, including the Korvat colony negotiations in 2289 and the Khitomer Accords of 2293. As a result, he formed a close relationship with several notable Klingon figures, including the warrior Kang, who eventually named his first son in honor of Dax.

Though unknown to most non-Trills at the time, Curzon Dax was a joined Trill, which meant that the humanoid individual contained a symbiotic creature that included the memories of its previous hosts. In the case of Curzon Dax, the humanoid individual was Curzon while the symbiote was Dax. The two became joined in the year 2286, following the death of Dax's sixth host, Joran.

''In a potentially alternate timeline, Curzon Dax would pass away in 2367, after which the Dax symbiote would be passed to its eighth host, Jadzia Dax, who would of course become a key figure aboard the Federation space station Deep Space Nine in the 2360s and 70s. It remains to be seen whether the Tempest version of Curzon Dax will experience a different history.''