Bertie Cecil, who is called "Beauty of the Brigades", is a young nobleman serving in the First Life Guard as a cavalryman. He leads a comfortable, upper-class life full of hunts and horse races, surrounded by a large admiring circle of influential friends. The only faults in his life are that his family is bankrupt and his brother Berkeley has a bad gambling problem.
When he loses a bet on a horse race, he has nothing left but his brother who signed a heavy bill with Bertie's name. Because he was with the 'titled and wedded' Lady Guenevere when the bill was signed, he has no way of proving that the signature is forged except with, at the same time, exposing Lady Guenevere. Such as to not ruin both Berkeley and Lady Guenevere's names, Bertie flees and joins the Chasseurs d'Afrique, where, after twelve years of service, he meets the fascinating camp-follower Cigarette as well as the ruthless Châteauroy, his commander, who is in love with Cigarette.
Her expressing interest in Bertie only worsens his treatment of the same, and the situation is made even more confusing when Princess Venetia Corona shows up, with whom Bertie falls in love after last having seen her when she was a very young girl.
Under Two Flags (1867) is one of the two most well-known works of English author Ouida, pen name of Marie Louise de la Ramée (the other is A Dog of Flanders) and spawned the genre of French Foreign Legion romances, the most famous of which is now Wren's Beau Geste, despite not even involving the French Foreign Legion.
It was adapted into four movies, the last of which starring Ronald Colman with Claudette Colbert as Cigarette, and an obscure comic book. The Goon Show play "Under Two Floorboards" is actually their version of Beau Geste, not this thing.
Under Two Flags contains examples of:
- Action Girl: Cigarette, oh so very much.
- As Long as It Sounds Foreign: Bertie joins the Chasseurs as the Frenchman Louis Victor.
- Author Appeal: The novel has many an autobiographical aspect.
- Beauty = Goodness: Bertie's nickname is Beauty for a reason. His evil brother Berkeley, on the other hand, has a weak chin.
- Betty and Veronica: Humble English princess Venetia is the Betty in this one, rash soldier girl Cigarette the Veronica.
- Bilingual Bonus: We hope you speak French. The characters certainly do.
- Book Dumb: Cigarette, again.
- Boyish Short Hair: One of Cigarette's distinguishing features.
- Cain and Abel: Berkeley and Bertie
- Camp Follower: Cigarette's official profession.
- Captain Smooth and Sergeant Rough: The dynamics between Bertie and Châteauroy resemble this.
- Embarrassing Nickname: Cigarette calls her friends and co-soldiers gros bebées, meaning big babies.
- Bertie's nickname Beauty is this to modern readers.
- Everyone Calls Him "Barkeep": Cigarette is not known by any other name.
- Everything's Better with Princesses: Venetia is called a princess for a reason.
- First Guy Wins: Venetia eventually marries Bertie.
- Good Adultery, Bad Adultery: It is clearly shown that Bertie's actions with Lady Guenevere were wrong, yet he is painted in a very positive light.
- Hello, Nurse!: Cigarette induces this.
- Honor Before Reason: Bertie in a nutshell.
- Impoverished Patrician: Bertie
- Incorruptible Pure Pureness: Princess Venetia
- Legion of Lost Souls: Despite being often mistaken for this by readers, the Chasseurs d'Afrique were nothing like the French Foreign Legion. The Legion, back then, were sleazy mercenaries, the Chasseurs were gentlemen. The films corrected this.
- Love Triangle
- Officer and a Gentleman: Bertie
- Qurac: The setting is very romanticised.
- Sergeant Rock: Châteauroy, who has no qualms about treating Bertie (and everybody else) very harshly.
- Smoking Is Cool: Cigarette being a smoker stressed her masculinity back in the day the book was written, it also illustrates her as a misfit or even vamp, yet she is clearly meant to be a very positive character.
- Taking the Bullet: How Cigarette dies.
- Trading Bars for Stripes: Bertie's motivation to join the Chasseurs is to not destroy the reputation of Berkeley, Lady Guenevere, and himself.
- Trope Maker: For the French Foreign Legion/desert romance genre.
- Tsundere: Cigarette, of the tsuntsun type.
- Who Names Their Kid "Dude"?: The book doesn't make it clear whether Cigarette is her real name, or if she's Only Know By Her Nickname.