In the mirror universe, Curzon Dax was a joined Trill, the seventh host of the Dax symbiont, who lived during the 23rd and 24th centuries. His birth name was Curzon Antrani. He was born in the 2260s. Shortly after being joined in the 2280s, Curzon became a member of the diplomatic corps of the Terran Empire and quickly gained a reputation as one of its diplomats who truly understood the Klingon mindset. He attributed this to the fact that he did not let the Klingons intimidate him. While other diplomats attempted to appease them, he challenged them. Although he was only in his twenties at the time, Emperor Spock appointed him as the ambassador to Qo'noS in 2286.