2138

According to the Star Trek Spaceflight Chronology, an interplanetary war near the Romulan Neutral Zone causes tensions between the Federation and the Romulan Empire to rise for the first time since the Earth-Romulan War. As the book is from 1979, it does, however, not acknowledge the facts, that neither the Romulan Neutral Zone nor the Federation will be founded until 22 years and 23 years later, respectively.