Romulan HistoryAbout 2000 years ago, Surak's teachings gained acceptance and led the previously violent Vulcans a new logical and peaceful way. This process lasted a century, until the logicians eventually prevailed (the time of the Awakening). In some unknown way, all this may have been triggered by a member of the Q Continuum. A small group of dissenters, counting several thousand, decided to leave Vulcan in sublight vessels. They were never heard of again on Vulcan until 2000 years later. Each generation reached a new planet where colonies were founded, but soon abandoned again. Barradas III, Calder II, Dessica II, Draken IV and Yadalla Prime were among them, and most of them are now in Federation space. They either subdued or merged peacefully with the resident Debrune civilization. This might be the reason why most, but not all Romulans have pronounced cranial bones unlike the Vulcans. Over five hundred years after their departure, the emigrants discovered the planet that should be later known as Romulus. Compared to the previous worlds, Romulus was a paradise, and the Romulans decided to stay. During the following centuries, the civilization flourished and grew very quickly. The barren neighbor planet Remus was within reach of the Romulan sublight ships and was conquered some time later. The Remans either come from this planet, or they are actually the indigenous population of Romulus and were later deported to Remus.
In the meantime, warp drive had been discovered on Vulcan. The Vulcans explored space within about 100ly around their homeworld, including Earth. When they picked up traces of the Romulans, they subsequently avoided them, as they avoided contact to any other pre-warp civilization. They probably knew that the Romulans were their descendants, but preferred not to care about them to preserve peace on Vulcan. Yet, a political movement to which V'Las belonged sought an informal contact with Romulus and possibly provided technical support for their fleet.
The Romulans discovered warp drive at about the same time Cochrane did or acquired it from the Vulcan conspirators. They founded colonies in several neighboring star systems, including Romii. The formal name "Romulan Star Empire" came into use. At some time in the 2150's the Romulan Imperial Fleet discovered several possibly dangerous threat forces, including Earth and the Klingons. They subsequently attempted to destabilize the diplomatic situation sending out unmanned cloaked drones to attack freighters of the various civilizations. Thanks to the intervention of Enterprise NX-01 with the support of the Tellarites and Andorians the Romulan scheme failed. Seeing their Empire endangered, the Senate decided to conduct a preemptive strike against Earth and care about the Klingons later. Earth didn't anticipate the Romulan attack, but with the help of their new allies, Tellar and Andor, they could finally defeat the Romulans. The Vulcans only provided supplies, but never engaged themselves in the hostilities, knowing well that this might lead to a destabilization of their now fragile society. Rumors that the Romulans might be the long-missing Vulcan emigrants were widely ignored for the alliance of Earth and Vulcan should not be endangered. Nevertheless, Starfleet was founded in 2161 against the wished of the Vulcans, and relations remained problematic even a century later when Spock was in Starfleet.
The Romulan war ended with the victory of the Earth Alliance. The Romulans, ashamed of their defeat, refused to take part in a personal talks, this is why the peace treaty was negotiated via subspace radio. The Romulan Neutral Zone was supposed to prevent mutual incursion. The Neutral Zone is one light year thick and is mostly composed of former Romulan territories, extending only a few light years from Romulus. In the subsequent years, the Romulans were also defeated by the Klingons who conquered several territories directly adjacent to the Federation. The Federation was very careful not to cross the Neutral Zone.
In 2266 a Romulan Bird-of-Prey equipped with a novel cloaking device and plasma weapon violated the Neutral Zone for the first time in a hundred years and destroyed four Earth Outposts (which were still called "Earth" and not "Federation" Outposts for historical reasons). This ship had warp drive which was necessary to reach the Neutral Zone, but could not use it while cloaked because of the enormous power consumption of the cloaking device. Thus, the cloaked ship was moving at impulse speed and didn't exhibit a warp signature. Moreover, it was powered by a fusion reaction (=impulse in Federation terminology), so Chief Engineer Scott's assessment that their power was simple impulse was correct in any case.
Hostilities between the Romulans and Klingons continued until a brief alliance was established in 2268. The Romulans acquired several Klingon ships, the Klingons received the Romulan cloaking technology in exchange. The alliance ended as soon as 2270 when the Klingons won the Battle of Klach D'Kel Brakt. Klingon technology helped the Romulans to significantly improve their starships. Nevertheless, the principle of a matter/antimatter warp core taken from the Klingons was later abandoned in favor of an artificial quantum singularity.
Thousands of Federation citizens lost their lives in the Tomed Incident in 2311. This was the incentive for a new treaty in which the Federation was obliged not to employ cloaking technology, while the Romulans withdrew several territorial claims. It was also the beginning of a new isolationist period in which the Romulans focused on strengthening their position in the Beta Quadrant, on the opposite side of the Klingon and Federation borders. While the Federation easily accepted this policy, there were several conflicts with the Klingons during that time, most notably over Khitomer and Narendra III. The Borg attacks on several outposts in 2364 ended the isolation.
(Theory by Bernd Schneider)