The tenth ''Asterix'' volume presents the military careers of the unlikeliest soldiers in the whole Roman army: Asterix and Obelix!

As Asterix and Obelix set out on a boar hunt, Obelix is distracted by fellow villager Soporofix's lovely daughter Panacea, who has just returned from studying in Condatum (called Rennes today), and the menhir deliveryman walks straight into a tree (to Dogmatix's dismay and Getafix's anger, the druid having been in the tree cutting mistletoe). When the duo return from the hunt, Obelix gets distracted by Panacea again, and only ends up eating two boars with Asterix before losing his appetite. Alarmed at his friend's change in demeanour, Asterix fetches the druid, and they pass Panacea on their way back... followed by Obelix, delivering a menhir he doesn't have. Getafix thinks he knows why Obelix is acting strangely, and when he calls Panacea back and (re)introduces her to our heroes, his suspicions are confirmed: Obelix is head over heels in love with Panacea! (Dogmatix doesn't approve.)

Asterix suggests that Obelix act on his crush, so he goes into the nearby forest to pick some flowers (and beat up a Roman patrol) to give to her. Asterix is about to leave his friend alone with Panacea when Postaldistrix the postman (seen in [[Recap/AsterixAndTheNormans the previous album]]) delivers a message revealing that Panacea's fiancé, Tragicomix, has been conscripted into the Roman army and posted to Africa. Obelix contains his heartbreak over discovering that Panacea already has a fiancé for just long enough to volunteer to bring him back, and Asterix volunteers to help. Vitalstatistix explains to them that their old friend Julius Caesar is fighting troops loyal to his political rival Pompey the Great near Ruspina (the Roman name for the Tunisian city of Monastir) and needs all the volunteers he can get - and if he can't get volunteers, he'll take draftees instead. Obelix leaves Dogmatix with Panacea until he and Asterix return - and one kiss from his master's crush, and Dogmatix is smitten too...

The two Gauls hurry to Condatum, hoping to rescue Tragicomix before he is posted, but upon arriving at the local army headquarters (and being given the runaround by the various departments when trying to get information), Asterix is informed that Tragicomix is already in Massilia (Marseilles) and will be shipping out to Africa any day. The only way to get him back is to enlist, so the two Armoricans join Neveratalos the Greek, Selectivemploymentax the Briton, Gastronomix the Belgian, Hemispheric and Allegoric the Goths (at least until the latter is rejected for being too skinny), and Ptenisnet the Egyptian (who thinks the headquarters is a hotel for tourists on a package holiday) in signing on for a tour of duty with the 1st Legion, 3rd Cohort, 2nd Maniple, 1st Century.

Medical inspection and kit distribution do not quite go off without a hitch, while Neveratalos starts an argument with the recruiting officer, Nefarius Purpus, over their meagre wages (two and a half sestertii per day), so that by the time the new recruits meet their drill instructor, Dubius Status, Purpus is reduced to tears... and Status follows in short order after the cookhouse trumpet sounds before he can get any training done. The new recruits (bar Selectivemploymentax) are disgusted by the terrible food, and one visit to the kitchen later, the Gauls have "persuaded" the cook to serve proper, if very unmilitary, meals. Dubius Status' mood deteriorates further when he tries and fails to drill the Gauls in military discipline and fighting skills, and even further the next day when our heroes lose patience with a route march with backpacks full of rocks and, one belt of magic potion for Asterix later, decide to carry their fellow recruits' packs while the other recruits carry their hapless DI.

Upon returning from the shambolic route march, the recruits are informed by Purpus that they are setting out for Massilia at once, to be posted to Africa. Seizing their chance to catch up with Tragicomix, Asterix and Obelix insist on marching straight through the day without stopping (to their officers' shock), and the next day they and their fellow recruits even change back into civilian clothes, so that by the time they reach Massilia, the two centurions are unshaven nervous wrecks. Asterix and Obelix's haste continues when they board a galley and insist on overriding the captain's orders by going full steam ahead to Africa (pausing for just long enough to sink the ship of Redbeard and his pirate crew, who previously thought a Roman galley easy pickings).

At Caesar's camp near Thapsus, the unmilitary behaviour of the new recruits continues as, one by one, they wander into Caesar's tent (Ptenisnet in search of activities; Gastronomix, Selectivemploymentax, and Hemispheric in search of beer; Asterix and Obelix in search of Tragicomix) as he plans strategy for a battle against Pompey's ally, Metellus Scipio. The two Gauls meet an older legionary who, in exchange for a drink, tells them that Tragicomix had only just arrived in Africa when he was lost in a fight with Scipio's forces; fortunately, the spy Vitriolix, who has just been on a reconaissance mission for Caesar, tells them that Tragicomix was taken prisoner rather than killed, and is being kept in Scipio's camp to the north.

Asterix and Obelix break out of their camp, and Caesar, convinced that the duo are spies planning to report back to Scipio, sends a patrol after them... and when said patrol hears the two Gauls fighting one of Scipio's patrols, they are convinced their opposite numbers are attacking, and Caesar rouses his armies to head into battle. The two Gauls smash their way into Scipio's camp, and when the lookout sees Caesar's armies right behind them, Scipio's forces head out to meet them. With the camp deserted, the two Armoricans are able to free Tragicomix from the prisoner's enclosure and return to Caesar's camp; as for the battle, since both armies are in the same uniform, there is so much confusion as to who is on which side that Scipio surrenders in disgust. The three Gauls change back into civilian clothes and run into Caesar on their way out of the camp again; grateful for their contribution to his victory over Scipio, the Roman leader gives the trio honourable discharges, and as their erstwhile comrades-in-arms bid them farewell, even Nefarius Purpus thanks Asterix and Obelix for their (inadvertent) aid.

The three Gauls board the same galley they took from Massilia (stopping to sink Redbeard's ship again on the way back) and return to their village, where the lovers are reunited. Before leaving to get married in Condatum, Panacea gives Asterix and Obelix a kiss of thanks. And while Obelix returns to normal, his good attitude and appetite restored, now it is Asterix's turn to be lovestruck, and he spends the banquet sitting in a daze in the branches of a tree.
* AllLoveIsUnrequited: Obelix and Asterix (and Dogmatix!) end up smitten by the beautiful Panacea... but although friendly toward them, she has eyes only for her fiancé, Tragicomix.
* AnimatedAdaptation: This and ''Asterix The Gladiator'' were fused to create ''Asterix vs Caesar''. Though the animated adaptation did make a few script changes. The Egyptian and the Greek were removed and replaced by a Spaniard instead.
* ArtisticLicenseHistory: The actual civil war between Julius Caesar and Metellus Scipio did end with the Battle of Thapsus, but it had a high body count and was followed by the suicides of Scipio and Cato the Younger. But Goscinny and Uderzo would never have dreamed of depicting such carnage in an ''Asterix'' volume, so they had the battle collapse into chaos instead.
* BodyCountCompetition: Between Asterix and Obelix, counted by Roman legionary helmets (continuing the RunningGag started in ''Recap/AsterixTheGladiator'').
* BolivianArmyEnding: Subverted, as Obelix merely punches through the Roman army that shows up once Tragicomix is broken out.
* BootCampEpisode: Asterix and Obelix join the army.
* CampCook: The unnamed cook at the boot camp, who joins the legionaries on the journey to Africa, appears to be a typical LethalChef, but he's cooking badly deliberately on the assumption that bad food will put the soldiers in a bad mood and make them more effective. One thumping from Asterix and Obelix later, and his standards improve dramatically (exacerbating the new recruits' thoroughly un-military demeanour).
* CosmeticallyDifferentSides: Averted, leading to lots of confusion when ''both'' sides get the order to form the testudo, and the order-relaying horn blowers ending up in the same place.
* DrillSergeantNasty: The Officers training the recruits try to be this, but Asterix and Obelix reduce them to tears.
* EnemyCivilWar: Rome, the usual antagonist in the ''Asterix'' series, was far from united even in her golden age, and this album gives a comic depiction of the civil war between Julius Caesar and Metellus Scipio.
* EveryEpisodeEnding: Cacofonix has been tied up as usual, but there's someone else sitting this one out... It's Asterix himself, in a lovesick daze.
* {{Expy}}: The maniple in which Asterix and Obelix serve to the French Foreign Legion. The training sequences are loosely based on those of the Foreign Legion (in particular the march with heavy packs where a squad has to finish the distance leaving no one behind), it contains [[Literature/BeauGeste people unhappy in love]], and they are sent to Northwest Africa.
* ForeignQueasine: The Roman soldier's meal is wheat, cheese and bacon cooked together to save time. Naturally, Selectivemploymentax the Briton is the only one to enjoy the stuff (he says it's just like the food back home). Asterix and Obelix threaten the cook into serving boars and cakes instead.
* IWantMyBelovedToBeHappy: Obelix, of course. While he puts on a stoic face for Panacea, once he and Asterix are out of view...
-->'''Asterix:''' Obelix, I'm proud of you! You were really brave! When you heard Panacea was engaged you didn't even...
-->'''Obelix:''' '''BOOHOOHOO! ''I'M SO UNHAPPY!'''''
* LethalChef: Averted. He's a talented chef who cooks badly on purpose. Once Asterix and Obelix confront him over the terrible food, he starts cooking much more luxurious and delicious food.
* LoveMakesYouCrazy: Panacea has a profound effect on Obelix; [[DistractedByTheSexy seeing her causes Obelix to walk into trees,]] [[DoesNotKnowHisOwnStrength knocking them over.]]
* MildlyMilitary: By virtue of resisting everything their commanding officers throw at them, the Gauls' company becomes this without having left Gaul.
* NationalStereotypes: The Goth (German) is dead serious and speaks in Gothic lettertype, the Greek speaks in Greek typography, the Egyptian speaks in hieroglyphs, the Belgian is jolly and petulant, the Briton is calm, polite and enjoys eating food that others find horrible.
* ObstructiveBureaucrat: Asterix gets the runaround from these in Condatum before losing his temper.
* OOCIsSeriousBusiness: When [[BigEater Obelix]] isn't hungry for more than two boars, Asterix becomes ''very'' worried.
* PaintingTheMedium: In all possible ways, including PictorialSpeechBubble for the Egyptian, SymbolSwearing, speech bubbles becoming flowery and stylized Greek and Blackletter for the Greek and Gothic speakers.
* PostKissCatatonia: Dogmatix, Obelix, and Asterix suffer from this, all courtesy of Panacea.
* RagtagBandOfMisfits: The company Asterix and Obelix are part of consist of Neveratalos the Greek, Selectivemploymentax the Briton, Gastronomix the Belgian, Hemispheric the Goth, and Ptenisnet the Egyptian who thinks he's joined a holiday camp. Subverted in that they don't accomplish much beside driving their [=COs=] to tears. This requires the company to have a Roman interpreter with them, and even he delights in winding up the Centurion.
* RecursiveTranslation: In-universe example that loses nothing. Obelix's too-small breastplate just struck Nefarius Purpus in the face...
-->'''Purpus''': [[SymbolSwearing @#$%]]!\\
'''Hemispheric''': ''[in Proto-Germanic]'' What did the centurion say?\\
'''Interpreter''': ''[in Proto-Germanic]'' He said "^&*+".\\
'''Purpus''': ''[in Latin]'' What did you say to him?\\
'''Interpreter''': "@#$%".
* RunningGag:
** Whenever a character breaks down in tears, somebody will ask if he's in love.
** A mix-up near the start of the album results in Obelix thereafter referring to hitting people as "being polite".
** A one-page gag involves all Asterix's company blundering into Caesar's tent thinking it's the local pub or the vacation camp headquarters or other non-military affairs.
--->'''Caesar:''' WHO ARE THESE PEOPLE!?
** "Tragicomix with a 't' as in '[[ Timeo Danaos et dona ferentes]]'?"
* SheIsAllGrownUp: As Panacea herself recalls, when she left to study in Condatum, she was just a little girl with her hair in pigtails. Asterix and especially Obelix are amazed at how different she looks upon her return.
* ShoutOut:
** When the Belgian legionary removes his helmet for a moment, he shows a [[Comics/{{Tintin}} familiar, red crest]].
** When the pirates' ship is sunk, they rescue themselves onto a raft in a panel that parodies Géricault's painting "The Raft of the Méduse".
* SustainedMisunderstanding: Ptenisnet the Egyptian wanders into the recruitment station thinking it's a vacation planning office. The recruiting Officer goes along with this so he joins. Along the entire story he thinks it's a large outing, ending with saying that it reminded him of his own time in the military.
* UnfortunateNames: Nefarius Purpus' name in the Latin translation (and therefore likely his true name) is {{Milesgloriosus}}.
* VacationEpisode: Asterix and Obelix travel to North Africa, then, in the AnimatedAdaptation, to Rome.
* VerbalTic: Selectivemploymentax the Briton has the same verbal tics his fellow countrymen had in ''Recap/AsterixInBritain''; he is barely able to get through a sentence without an "I say", "rather!", or "what!", using them almost as punctuation.