 Novelist Gary Cox first mentioned the events of the Eugenics Wars in his non @-@ canon novel Assignment : Eternity , which followed up on the events of the episode " Assignment : Earth " and included the characters of Gary Seven and Roberta Lincoln . In it , he mentioned that Seven and Lincoln were involved in overthrowing Khan during the Eugenics Wars . He had not intended to explore this any further , but he was prompted to do so by his editor at Pocket Books . He wrote a story , split into two books , about the specific events of the Eugenics Wars , entitled Star Trek : The Eugenics Wars : The Rise and Fall of Khan Noonien Singh . As the Eugeneics Wars were already meant to have taken place , he decided to describe them as being a massive conspiracy that was not discovered until generations had passed . He also felt that this approach would make the books consistent with the Star Trek : Voyager episode " Future 's End " in which the crewmembers travel in time to the same period of Earth 's history as the Eugenics Wars , but find no such wars taking place . A further version of the Eugenics Wars was presented in the Star Trek : Khan comic book mini @-@ series . 
