The Romulan Star Empire was the primary state of the Romulan people. Its capital was the planet Romulus in the Beta Quadrant and it was governed by the Romulan Senate. A highly secretive state the Romulan Empire was known for its xenophobic and hostile attitude towards other species.
During the 2150s the Romulan Star Empire went to war with United Earth. With its defeat a neutral zone was established between the empire and Earth. The empire then entered a prolonged period of isolation.
During the mid-23rd century, the Romulan Star Empire left its isolation, returning to the galactic scene. During this period it joined in an alliance with the Klingon Empire trading its cloaking technology for powerful Klingon D7 class cruisers.
In 2311, the Tomed Incident between the United Federation of Planets and the Romulan Empire led to the Treaty of Algeron between the two powers. One of the components of the treaty was a ban on the Federation developing and using cloaking technology. Following this the Romulans again entered a extended period of self imposed isolation.
While the Romulans had mostly left the galactic scene they periodically clashed with their neighbours. Following a series of attacks by an unknown force, later believed to be the Borg, along the Neutral Zone led to the Romulan Empires re-engagement with the Federation.
Initially after the Dominion entered the Alpha Quadrant the Romulan Empire stood against them, deploying starships to Deep Space 9 to join the Klingon and Starfleet forces to defend against what they believed to be a Dominion attack against the space station. Several month later the empire signed a nonaggression pact with the Dominion and when the Dominion War began in earnest in late-2373, the Romulan Empire was not involved.
In mid-2374, the Romulan Star Empire entered the Dominion War joining the Federation Alliance. The Romulans' entry into the war was sparked by the assassination of Senator Vreenak and the discovery of a Cardassian isolinear rod that seemed to show a Dominion plan for a surprise invasion of the empire. The Romulans assumed that Vreenak had come across the information during a visit to Cardassian space and had been killed by the Dominion to prevent the information from returning to Romulus. In reality, the information on the rod was a forgery as part of a plan by Starfleet Captain Benjamin Sisko to bring the Romulans into the war on the Federation's side.
In 2379, the Romulan Senate was assassinated and Shinzon backed by part of the Romulan military and the long subjugated Remans took power. Shinzon almost took the empire to war with the Federation with his plan to attack Earth and devastate it with a thalaron radiation weapon. Shinzon's plans were thwarted and he was killed during the Battle of the Bassen Rift.
- ↑ 1.0 1.1 TOS: "Balance of Power"
- ↑ TOS: "The Enterprise Incident"
- ↑ TNG: "Reunion"
- ↑ 4.0 4.1 TNG: "The Neutral Zone"
- ↑ TNG: "The Pegasus"
- ↑ TNG: "Yesterday's Enterprise"
- ↑ Swiftfire: "First Choice"
- ↑ DS9: "By Inferno's Light", "Call to Arms"
- ↑ DS9: "In the Pale Moonlight"
- ↑ DS9: "What You Leave Behind"
- ↑ Star Trek Nemesis