Romulans, also known as Rihannsu, are a Beta Quadrant race from the planet Romulus (ch’Rihan). As a branch of the Vulcan species, Rihannsu have pointed ears and upswept eyebrows. Many, but not all, possess a small V-shaped ridge above the bridge of their nose, uncommon to Vulcans. Males have softer facial features than Vulcans. The height of Rihannsu males range between 5'7" to 6'3" and their weight is between 145 to 250 pounds. The males have strength two to three times greater than that of the average non-Rihannsu humanoids. The height of Rihannsu females range from 5'6" to 5'9" and weigh between 126 to 165 pounds. There are a few exceptions as in any race, however Rihannsu females are, like the males, generally of greater strength then those of other races. Like Vulcans, Rihannsu blood is green when oxygenated in the arteries and is copper or rust colored when deoxygenated in the veins. The Romulan heart is gray. The maximum Rihannsu lifespan that can ever be expected is approximately 250 standard years, with more typical figures ranging from 200 to 230.
Rihannsu society is matriarchal and based on a highly structured caste system. At the center of the Rihannsu code of behavior is the importance of "Mnhei'sahe." It is an abstract measurement of a Rihannsu's personal honor and is often used as a status symbol in their culture. Mnhei'sahe, which translates loosely to "the ruling passion," centers around a strong respect and appreciation of honor, duty, courtesy and strength. In all interactions between Rihannsu, it is imperative that all parties leave afterward feeling that their honor and "face," is intact. If not, it is paramount to denying mnhei'sahe to the offended party. If the offending party feels he can apologize without himself losing face, he does so. Wars, executions and deaths of entire households can be required to satisfy mnhei'sahe. If mnhei'sahe is always intact within the Empire, the Rihannsu believe that they can never lose.
If the disgraced party is beyond redemption, those present may simply execute him or allow him to commit ritual suicide, in order prevent further disgrace and loss of mnhei'sahe. It is not a specific set of rules, but an unspoken understanding which guides the actions of all Rihannsu throughout life. Rihannsu honor their word when it is given to another. To break with one's word means dishonor and a loss of mnhei'sahe, a fate worse than death. Politeness, respect, and quiet dignity are always required if mnhei'sahe is to be satisfied. The worst thing that can happen to a Romulan, worse than death is dishonor, and to have their name removed from House records and State records, showing they are no longer a citizen of the Empire.
Rihannsu honor power as much as they honor loyalty. If not for one's self or House, then always for the Empire. Rihannsu are always loyal to the Empire itself, not to any one person. For the Rihannsu, power cannot be defined in standard Terran terms, but in the power of mnhei'sahe, and it defines the very structure of Rihannsu society.
Status is ordered according to rank, house status and personal accomplishments in a long chain until ending with the lowest status, that of a prisoner. Prisoners are considered even lower than slaves - a prisoner is without honor and is not fully Rihannsu.
It is rare for any two Rihannsu to have the exact same social standing. Although prestige and social standing are often related to rank, social status should not be confused for military chain-of-command. Ranks affect social structure, not vice versa. The way things are set up is to ensure that no Romulan is on an even setting with another. Two erei'Arrain's are not equal. The erei'Arrain that has held the rank longer is considered the superior officer.
Romulans place a lot of stock in where they are both in the military and in their houses as well as where their houses are in society. They have a caste system and are loosely based on the Roman Empire. Great Houses have more say / money / etc. than Lesser Houses and Lesser Houses have more say / money / etc. than the peasant class.
There are many methods of which an individual may rise in status: merit and achievements (as well as military honors), subterfuge and betrayals (including blackmail and strategic use of personal or political secrets), the gaining of powerful allies, "elimination" of opponents, wealth (buying of support) and pressure tactics.
While the military plays an important role in Romulan society, it is the Romulan Senate that controls the government. The Romulan Star Empire is a republic.
The highest Romulan rank is the Praetor, who presides over the Romulan Senate and acts as chief of the executive branch. The Praetor heads the Continuing Committee, which is comprised of the Empire's most elite individuals, which make decisions of the utmost importance.
By the 24th century, the government of Romulus is dependent upon the Tal Shiar, the Federal Intelligence Agency of the Rihannsu Empire, to maintain order and stability among both civilians and the military. They have a broad scope of power, extending into all walks of Rihannsu life, and all citizens are assured in their safety, knowing the Tal Shiar are everywhere, watching for disloyalty and/or threats to the Empire. The Tal Shiar is known for its brutal tactics, which include routine kidnapping, torture, and assassination. Many Romulans fear even expressing dissenting opinions as to not spark the interest of the Tal Shiar. They are considered above the law and are responsible for ensuring the loyalty of ALL citizens, even high placed government officials and military personnel.
The Tal Diann is Military Intelligence, as opposed to the Tal Shiar, which is civilian. It is the Romulan Star Command’s internal affairs division, and as such, fills a multi-function role in the Romulan Star Navy. The Tal Diann polices its own, and operates counter-intelligence operations against the Tal Shiar. They maintain and monitor relations between the Star Command and the various fleets, as well as between fleets themselves.