Olivier Mira Armstrong

Major General Olivier Mira Armstrong (オリヴィエ・ミラ・アームストロング, Orivie Mira Āmusutorongu) is Alex Louis Armstrong's older sister. She is in charge of keeping peace on the northern borders of Amestris from her domain, the Briggs Fortress.

Olivier is a dauntless woman who scoffs at the concept of "equivalent exchange" and believes "survival of the fittest" is the only law in life. Her subordinates are incredibly loyal to her, however, if their attachment to her were to ever put Briggs at any open risk, they are instructed to leave their leader behind. She despises Colonel Roy Mustang and is brutal towards her little brother, considering them both to be weak and insulting to the state military. Perhaps her closest subordinate and friend is Major Miles, a man of mixed blood with great appreciation towards the General.

Olivier is first introduced when Edward and Alphonse are sent north with a letter of introduction from Alex to see his older sister. Once in the frigid, snowy plains of the Briggs Mountain range, they are attacked by Buccaneer (believing them to be Drachman spies), and taken before the General herself. Olivier is quick to dismiss her brother's letter and informs the two brothers that she only judges people with her own eyes.

When the Homunculus Sloth accidentally infiltrates the fortress, Olivier uses this opportunity to test the Elrics' loyalty. Mounting a Briggs Tank, General Armstrong leads the defense against the intruding Homunculus, eventually freezing him solid with the harsh weather of the region to her advantage. Now working more closely with the Elrics -- who she suspects might still be withholding information from her -- Olivier is informed of the Nationwide Transmutation Circle, and Central's sinister plans which also seem to threaten her northern soldiers. Fortunately, with the unexpected arrival of General Raven from Central High Command, Olivier decides to prod in deeper into the military's true intentions. Raven, taking the bait, attempts to seduce Armstrong with promises of an "immortal legion" at her command if only she pledged full allegiance to Central.

With her true target now made clear and a determination to save her base and soldiers by her own hand, Olivier kills the corrupt General (who had also ordered her to set Sloth free earlier), and answers Führer King Bradley's personal summon. Once in Central City, she confronts him about his true nature and for her boldness is given Raven's seat at Central Command. Working as a sort of double-agent, Armstrong acts the part of ruthless leader if only to obtain the finer secrets of the military for her advantage. In time she is shown the "immortal" lesser Homunculi army by General Gardner and even comes face-to-face with Father himself.

Back at the Armstrong mansion, Olivier asks Philip Gargantos Armstrong to immediately retire and go on an extended vacation, and after defeating Alex Louis Armstrong in an inheritance brawl, she receives the estate. While visiting to congratulate her, Roy Mustang jokingly comments on the large space of the house and how it could easily fit a battalion inside -- a hidden tip she takes as the Briggs forces covertly move into the large mansion in preparation for the inevitable coming conflict.

When Mustang begins his attack on the city, Olivier is located in Central Command, where she openly mocks the corrupted Generals and their misplaced sense of security. After shooting down Gardner, she takes on another General as a hostage, a move which ultimately proves useless when Sloth reappears and terminates the General in his attack. Thanking the Homunculus for preventing her from having to "dirty her blade with that scumbag's filthy blood", she fearlessly fights against Sloth and the lesser Homunculi hordes, soon joined by her brother and then by the soldiers sent to kill her whom she convinced to "Act on their own for once". After a long and hard fight, they are saved by Izumi Curtis and her husband, who effectively manage to kill Sloth.

Powers and Abilities
Being the General of Briggs, Olivier has full command of the Fortress. She is also very skilled with her family heirloom sword which she uses unhesitatingly. She also seems to have some proficiency with tanks and other heavy artillery, as she has been shown shooting bazookas with deadly aim. She is also, like the rest of the Armstrong family, very strong despite her appearance, and is even shown to be stronger than her brother Alex when she effortlessly defeated him while fighting for the head of the Armstrong Family.

Trivia

 * Like nearly all military personnel in the Fullmetal Alchemist series, the Armstrong family is named after a military vehicle, vessel or weapon, in this case, the Armstrong Whitworth Whitley (A.W.38 Whitley), a British bomber from early WWII
 * Major General Armstrong's first name, Olivier (オリヴィエ Orivie), is actually a masculine name. It is the French form (pronounced o-lee-VYAY) of Oliver.
 * She has a noticeable hatred to be accused or given anything that is considered feminine, where she will immediately destroy such gift (such as a bouquet that Roy Mustang gave her with flowers that in their name mean feminine). Appearing to hate being called feminine as much as Ed is being called short.