Fullmetal Alchemist: Brotherhood is known for its large and beloved cast of characters, from the Elric brothers who steer the main plot, to supporting characters like Roy Mustang and Olivier Armstrong, who are undeniably crucial to the events that unfold as the story continues. And the latter has become a fan-favorite side character, if only because of her fierce attitude and sharp tongue.

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But while Fullmetal Alchemist fans often see Olivier barking commands at her soldiers or showing off her prowess on the battlefield, they don't necessarily get the full picture of who she is solely from watching the anime.

Here are 10 things you probably didn't know about Olivier Armstrong.

10 10. She's The Highest Ranked Woman In The Anime

Fullmetal Alchemist has some pretty amazing female characters, but when it comes to climbing the ranks of the Amestris military, Olivier Armstrong has come the farthest. Not only is she the highest-ranking woman introduced over the course of the series, but Olivier is also the only woman in Central's High Command.

While these accomplishments are impressive on Olivier's part, they aren't that surprising. After all, she is a fierce fighter and leader, as well as an intelligent strategist. She's likely needed her quick wit and intimidating demeanor to remain on an equal playing field with the men in the military, and she's used them well.

9 9. She's The Only Person Edward Doesn't Yell At For Calling Him Short

It's no secret that Edward Elric gets called short a lot over the course of Fullmetal Alchemist: Brotherhood, and he's usually quick to start shouting at the perpetrator. However, this isn't the case with Olivier. She's actually the only character in the series who can call Ed short without sending him on a tirade — an impressive feat if there ever was one.

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Olivier's comments aren't just met with indifference either. Ed is typically too scared of Olivier to show anything but fear when she speaks to him. Given that she has such a formidable demeanor, we can't really blame Ed.

8 8. Olivier's Sword Is A Family Relic

FMA Olivier Sword

The Armstrong family is a proud one, and their pride in their heritage is immediately evident in their actions and words. They have family relics that are passed down through generations, and Olivier's sword is one such object. A saber that she wields impressively over the course of the anime, the sword makes an impression on viewers — particularly given the symbols that line the blade.

Since Olivier is the heir to the Armstrong line, it makes sense that she'd be the one gifted with such a relic. After all, Alex has alchemy to defend himself with. Olivier is better with hand-to-hand combat and swordsmanship, allowing her to better use the saber.

7 7. She Has A Rollercoaster Of A Relationship With Her Brother

Despite their strong familial ties, Olivier has a rollercoaster of a relationship with her brother Alex. Whenever the two see one another, it's clear that their bond falls somewhere between rivalry and contempt. Though Alex tends to view his sister with admiration, she often insults and belittles him — something that many fans have attributed to his "failure" during the Ishvalan Civil War.

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Still, even with her frequent criticisms of Alex, Olivier eventually admits to begrudgingly respecting her brother later in the series. Their feelings for one another are the epitome of complicated. Given all the entertaining moments this relationship gives fans, we wouldn't have it any other way.

6 6. Her Name Means "Olive Tree" In French

Olivier's name comes from the French phrase "olive tree," something that seems to bear little significance to her role in Fullmetal Alchemist, even if it is a pretty meaning. What is interesting, however, is that Olivier’s name actually takes on the masculine form in French. For that reason, she’s called Olivia in the French version of the anime.

Given that Olivier does tend to exhibit more traditionally masculine traits, though, it’s a strange coincidence that her name takes on a masculine form. It almost makes one wonder if it was an intentional choice.

5 5. She's Often Referred To As "Ice Queen"

Olivier's bad side isn't one that most sensible people would want to find themselves on, and her spiky personality isn't the only reason she can be intimidating. She’s also willing to make sacrifices for the greater good of Amestris, even if those sacrifices are her men’s lives.

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Olivier’s cold outlook and demeanor earned her the nickname “Ice Queen” among the soldiers. Well, that, and the fact that she’s stationed at Fort Briggs, in snowy Northern Territory.

4 4. She Does Have A Sympathetic Side

Even if Olivier is an “Ice Queen” at heart, she does still have a sympathetic side. It’s just buried deep down and viewers only see it on rare occasions.

There are several moments during Fullmetal Alchemist: Brotherhood when fans can tell that Olivier does feel guilt and sorrow for the losses the military suffers, even if she views them as a means to an end. She also clearly cares for her brother despite all of her vapid comments about his character. There’s proof Olivier has a heart; fans just need to search for it.

3 3. She Dislikes The Notion Of Equivalent Exchange

Olivier is one of the powerful characters in Fullmetal Alchemist: Brotherhood who doesn't use alchemy to fight her battles. Olivier uses her combat skills to defeat her enemies, and she actually looks down on alchemy and the concept of equivalent exchange.

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Her point of view is certainly a unique one, but it comes from her distaste for any type of weakness. For whatever reason, Olivier views the ability to create something using alchemy as the equivalent to receiving handouts, even though the law of equivalent exchange ensures that some sort of equal pay is always collected.

2 2. She Has A Longtime Rivalry With Roy Mustang

Roy Mustang is probably the only person Olivier treats worse than Alex. She and Mustang seem to have a longtime rivalry, with both of them always looking to show the other.

Of course, Mustang treats their rivalry as a playful sparring match, though whether he does this because he knows it aggravates Olivier more remains an option. She, on the other hand, seems to harbor genuine contempt for the Colonel.

olivier fullmetal alchemist

In a recent popularity poll, Olivier came in as the ninth most popular character from Fullmetal Alchemist: Brotherhood. It's hard not to like her with her terrifying sass, so it makes sense. While her ranking varies depending on the poll, in terms of the franchise's most popular female characters, Olivier typically competes with Winry Rockwell and Riza Hawkeye.

The other women have a greater presence in the series, while Olivier's role is slightly more limited. Her personality also might not impress all fans, especially those who don’t enjoy hearing a barrage of insults thrown at their other favorites.

NEXT: Fullmetal Alchemist: 10 Facts You Didn't Know About Armstrong