The Romulan Star Empire. Less logical than the Vulcans and less honorable than the Klingons, the Romulans went from a faceless enemy of the burgeoning Federation to a serious political adversary and eventually an uneasy ally. They’ve been described as “predictably treacherous,” but it has also been noted that they have “a strict moral compass.” The race was created for Star Trek: The Original Series (TOS) by Paul Schneider, inspired by Earth’s ancient Romans, and they have appeared in every iteration of Trek since, except for the Kelvin timeline films and the recently begun Star Trek: Prodigy (PRO). How much do you know about this enigmatic species? Read on to test your knowledge. And just a heads-up: there is a minor Star Trek: Picard (PIC) SPOILER lurking below. You’ve been warned!

The very first Romulan we ever encountered (in “Balance of Terror”, TOS) was played by Mark Lenard in the first of his Trek hat trick. Lenard’s Romulan Commander (proper name unknown) was attempting to carry out a mission of which he did not approve.

What was the mission and why did he have a problem with it?

The Romulan Commander’s superiors had instructed him to test the Federation’s defenses and resolve. To that end, he crossed the Neutral Zone and began attacking Earth outposts. The Commander believed that a Romulan-Federation war would bring too great a toll to his beloved Star Empire, but his sense of duty meant that he followed his orders to the letter.

After playing the Romulan Commander, actor Mark Lenard went on to play Spock’s father, Sarek, in several episodes and films, and then appeared as a Klingon captain at the beginning of Star Trek: The Motion Picture (TMP).

If you want to discover how things went down prior to the episode, you can check out John Byrne’s (non-canonical) comic “Alien Spotlight: Romulans.”

As the Dominion began to become more of a threat in Star Trek: Deep Space Nine (DS9), Starfleet decided that, instead of leaving Deep Space Nine’s crew hanging in space to become sitting ducks, they should be given a way to fight back, and thus were assigned an escort-class vessel, the USS Defiant. Among its sundry assets was a cloaking device, lent to Starfleet by the Romulans. Nothing comes without a price, though.

What was the caveat the Romulans attached to the loan?

The Romulans thought it best to help stop the Dominion but didn’t want Starfleet learning too many of their secrets. Therefore, it was understood that any time the Defiant went out, the crew was to take Subcommander T’Rul, a Romulan operative who would be the only person allowed to operate the cloaking device. T’Rul’s involvement lasted exactly two episodes (“The Search, Parts I and II”) before she was never seen or heard from again. A bit of a shame, as a Romulan operative on a Starfleet vessel could have shaken things up a bit and inspired interesting stories, but I wouldn’t feel too bad for the actress who played T’Rul. Martha Hackett went on to portray Seska, a recurring villain, in Star Trek: Voyager (VOY).

Imagine waking up one morning. You don’t feel quite yourself, but you can’t place why. You arise and carefully move through your dark room to the mirror on the wall. A light pops on, illuminating your face. But it’s not your face. The basic bone structure is yours, but there are points on your previously oval-shaped ears, there are V-shaped ridges on your forehead and your eyebrows, no longer following the curve of your eye, are at straight and positioned at a severe angle. Counselor Deanna Troi doesn’t have to imagine it; she lived it!

What the heck happened?

In “Face of the Enemy” Star Trek: The Next Generation (TNG), Troi was kidnapped by the Romulan underground in an elaborate plot to enable Romulan Vice-Proconsul M’Ret to defect to the Federation. Troi had been surgically altered to appear to be Tal Shiar agent Major Rakal and coerced into impersonating her as part of the plan. Odds are she needed some counseling herself after the incident.

There’s a reason Romulans and Vulcans share some physical traits, like the pointed ears and angled eyebrows. They used to be a single race.

What caused the split that made the Romulans who they are in Star Trek?

Two thousand years before our heroes began exploring the galaxy, Vulcans were wild and savage. A violent civil war began, and nuclear weapons nearly destroyed the Vulcan people. Out of this “Time of Awakening,” as it came to be called, emerged a gentle man named Surak. He fathered the Vulcan philosophy of peace and logic and brought his people out of the darkness of war. Not all Vulcans believed in his teachings and those that didn’t got in their ships and left the planet, ultimately settling on the planets Romulus and Remus and began referring to themselves as Romulans.

Remember that time when the Romulans cloned Jean-Luc Picard? Boy, that sure backfired on them. Before he could age enough, though, the Romulan government changed hands, the plan to replace Picard went by the wayside and the clone, Shinzon, went to a life of slavery on Remus. He quickly rose to become the leader of the Remans and masterminded a coup d’etat that left him in control of the Romulan Senate. He had quite the ship, too, sporting 52 disruptor banks, 27 photon torpedo bays, two separate shield systems and a cloaking device!

How did our intrepid crew locate Shinzon’s ship, the Scimitar, through its cloaking device?

The Remans, an offshoot of the Romulans, had inherited great telepathic powers from their Vulcan ancestors. Shinzon’s Reman Viceroy had earlier telepathically assaulted Troi, and now it was time for her to turn the tables. She located him using the same telepathic trick he had pulled on her and was able to triangulate the Scimitar’s position through its cloak. With the position obtained, Worf was able to fire on the invisible ship with remarkable accuracy.

In Star Trek: Picard (PIC) season one, we meet Elnor, an orphaned survivor of the Romulan supernova event. He had been trained from childhood by the Order of the Qowat Milat. But trained in what?

Who were the Qowat Milat, and what was their philosophy?

The Order of the Qowat Milat is a group of Romulan warrior nuns. They taught Elnor the Way of Absolute Candor, which basically means they have no filter. Whereas regular Romulans played things close to the vest, only revealing their motives when it was most beneficial to them, the Qowat Milat said everything they were thinking without omission. They were extraordinarily skilled single combat fighters who only attacked after issuing the plea, “choose to live.” If what we’ve seen of their battles are any indication, few of their opponents ever made that choice.