Seventeen years after Julian the Apostate, so-named for his efforts to revive Hellenistic paganism, was slain on the battlefield, Nicene Christianity has become the state religion. His old teacher Libanius bemoans this and proposes to Julian's old friend Priscus that they write a biography using Julian's unfinished memoir.
The memoir, with margin notes by Libanius and Priscus, tells Julian's story covering his youth as a royal hostage to his ascension to Caesar and then Emperor. Despite early successes in his reign, Julian's headstrong and superstitious nature begins to affect his decisions, culminating in a disastrous invasion of the Sassanid Empire, and his death.
The novel is known for its vivid detail in bringing the Ancient World to life, and especially for its portrayal of Roman society without the Hollywood History typical of most historical recreations. Indeed Vidal spent years researching the life of Julian and famously published a bibliography of reference material at the end of the text to serve as a guide to critics and scholars.
- Ambition Is Evil: Or at least, Ambition is Deadly. Julian triumphs repeatedly during his Persian campaign and almost gains a settlement with the Persians that would by even Maximus's admission be one of the greatest triumphs a Roman Emperor has won. But Maximus then plays on Julian's ambition to surpass Alexander, no settlement is reached, and Julian dies in Persia.
- Apocalyptic Log: Julian's diary entries and notations during the invasion of Persia.
- Ax-Crazy: As Caesar in Antioch, Gallus has a habit of stalking the streets and either fantasizing about murdering people or actually murdering them.
- Badass Beard: Subverted with Julian, who insists on combing his long beard into a point (Everyone tells him it looks ridiculous).
- Badass Bookworm: Julian is noted to be strong in spite of his bookishness, and proves himself to be a capable commander in Gaul
- The Caligula: Gallus, although sociopathic to begin with, loses it completely once he becomes Caesar. Libanius muses that it was almost as if he and his wife studied the histories of past tyrants just so he could imitate them.
- The Conspiracy: The plot to kill Julian on campaign is backed by several of Julian's senior officers, including future emperors Valens, Valentinian, and Jovian.
- Decadent Court: What was the deal with that imperial robe—the one that got a deacon killed? You order the wrong color garment (in this case, the same as the Emperor's), and are immediately found guilty of treason? The tailor is executed too. Better safe than sorry, we guess. Literally no one is safe in Rome.
- Death of the Old Gods: Hellenistic Religion, the Greek and Roman Pantheon are on their last legs. Their shrines and temples are used as roadside privies and their rituals have become gaudy exotic spectacles for tourists. Indeed when Julian dispatches a man to consult an Oracle at Delphi about whether his attempt to restore classicism will survive, the Oracle (called the Pythoness) states:Tell the King: on earth has fallen the glorious dwelling, and the water-springs that spoke are still. Nothing is left the god, no roof, no shelter, and in his hand the prophet laurel flowers no more.note
- Deliberate Values Dissonance: Several. Among other things, Julian is OK with some persecution of the Christians, with limiting peasants into family careers, and with the existence of slavery.
- Dirty Old Man: Priscus has an eye for the ladies.
- Dropped a Bridge on Him: Things look bad for poor Julian. As he spends his time writing letters to every senate he can think of, Constantius has the biggest army on Earth. Two of his legions desert him, and leave a fatal gap in his defense. Julian finds himself in despair, knowing that the gods have left him. And then Constantius dies of a fever. But not before making him his heir. Just like he did in real life.
- Dying Curse: During Maximus's trial for practicing magic, he said that the one to put him to death would suffer an ignominious end. The emperor who executed him, Valens, was cut to pieces by the Goths at Adrianople.Priscus:Right to the end, Maximus was lucky in his predictions.
- End of an Age: The book highlights Julian's brief reign as the end of the Ancient World with Christianity setting a Reset Button and changing civilization forever. Hellenistic religion, despite Julian's fervent efforts to revive it, is in total decay and in the end it will die out.
- Eunuchs Are Evil: With the exception of Mardonius, who helped raise Julian after his father died, the eunuchs are this. Julian is more than happy to purge them.
- Fatal Flaw: Julian's craving for the supernatural.
- Fictional Document: Julian's memoir, supposedly dictated each night while campaigning in Persia.
- A God Am I: Perhaps the worst thing Maximus does is to convince Julian that Cybele had spoken to him, telling him that she'd send the spirit of Alexander the Great to guide him, and that his victory is assured. This gets him into trouble.
- Got Volunteered: Literally in the case of Julian, who is offered a choice between declaring himself Augustus of the West, or being murdered by his Gallic legions. It's unclear whether or not Julian is embellishing events to disguise his ambition.
- Heroic BSoD: Julian has one when he thinks he's being set up to die in Gaul, and another when he realizes that the invasion is lost.
- Hijacked by Jesus: It's noted several times that the key to Christian success is their willingness to assimilate any pagan holiday or custom that invites new blood.
- Hypocrite: As pointed out numerous times by Julian himself and Libanius and Priscus, many Christian rituals and rites borrow wholesale from the despised "pagan" practices of Hellenistic religion. Julian also criticizes them for their endless schisms and their persecution of Jews.
- Incest Is Relative / Unholy Matrimony: Gallus and Constantina.
- Incest Subtext: In-Universe and Lampshaded. Priscus and Libanius note that Julian seems somewhat enamored of Gallus's looks, and is therefore somewhat more forgiving of his brother than he ought to be.
- Insane Troll Logic: Gallus says the following while talking to― at― Julian:Sometimes at night, I walk the streets in disguise. I listen to them. I watch them, knowing I can do anything to them I want and no one can touch me. If I want to rape a woman or kill a man in an alley, I can. Sometimes I do. But it is evil. I know it. I try not to. Yet I feel that when I do these things there is something higher which acts through me. I am a child of God. Unworthy as I am, he created me and to him I shall return. What I am, he wanted me to be. That is why I am good.
- Jesus Was Crazy: Julian's view is that Jesus was just some guy who thought he was the Messiah. He acted out the prophetic requirements, such as riding into Jerusalem on a donkey, and eventually resorted to violence when nothing else worked.
- Jesus Was Way Cool: Julian admits, grudgingly, that his moral teachings are beyond criticism though he notes that it's fairly simplistic compared to Plato and Aristotle.
- King on His Deathbed: Constantius and Julian.
- Leeroy Jenkins: Julian gives Libino half a legion and orders him to negotiate with a German King. On the way, he meets a German force five times his own. He promptly orders an attack, and he and his Romans are massacred.
- Lonely at the Top: Constantius writes Julian a poignant letter to this effect while on his deathbed. Julian had to deal with this even before became Augustus, but more or less reconciled himself with it.
- Make an Example of Them: The Deacon, killed for the cloak, and Ursulus, killed for badmouthing soldiers.
- Modest Royalty: Julian takes up celibacy and asceticism.
- Naughty Nuns: The "Shrine Of Aphrodite", where one can enjoy a priestess for a price. "They pretend it is religion. Actually, it is mass prostitution."
- No Hero Discount: The 'margin notes' repeatedly note Priscus' exorbitant fees in exchange for pages from Julian's memoir.
- No Social Skills: Constantius is actually rather dull and quite shy. He can only interact with others as Emperor. This is in sharp contrast to Julian.
- Off with His Head!: Gallus' punishment.
- Passive-Aggressive Kombat: Libanius and Priscus' constant snarking.
- Pet the Dog: Emperor Theodosius, devout Christian and fervent persecutor of pagans, decides to legitimize Libanius's bastard son, partly as consolation for refusing to publish his biography of Julian.
- Phony Psychic: Maximus. Picture BRIAN BLESSED in a toga, waving a staff around and pretending not to be useless. (His bogus fortune-telling is a direct cause of Julian dying on the battlefield, and Maximus is later convicted of heresy by the new regime.)
- Roaring Rampage of Revenge: Daglaif and his German/Gallic troops butcher hundreds of Persians in misplaced retribution for Julian's death.
- Romanticism Versus Enlightenment: Vidal is firmly on the side of the Enlightenment with Libanius and Priscus essentially serving as stand-ins as critics of the Emperor Julian's romantic dreams of single-handedly restoring antiquity against the tide of history and society. In the end, Julian became the embodiment of the end of antiquity with all his plans and reforms overturned on his death, while Libanius realizes that the classic world of Hellenism and antiquity has lost to Christianity, but he takes hope in the expectation that one day Christianity too will decline and lose favor among the people, much like the Gods it had replaced:''The world Julian wanted to preserve and restore is gone...but I shall not write "for ever", for who can know the future? Meanwhile, the barbarians are at the gate. Yet when they breach the wall, they will find nothing of value to seize, only empty relics. The spirit of what we were has fled. So be it...With Julian, the light went, and now nothing remains but to let the darkness come, and hope for a new sun and another day, born of time's mystery and man's love of light.
- Royals Who Actually Do Something: Julian, as both Caesar and Augustus, leads his soldiers himself, even personally leading assaults against fortresses in his Persian campaign.
- Shut Up, Kirk!: Libanius' exchange with Saint John of Chrysostom, an important Church father (and an ex-student of his), who notes that Christianity has definitively taken root in Europe for good:Saint John Chrysostom:"Do you see no significance in our victory? For we have won. You must admit that."
Libanius:"The golden age ended. So will the age of iron, so will all things, including man. But with your new god, the hope of human happiness has ended."
Saint John Chrysostom: "For ever?"
Libanius: "Nothing man invents can last for ever, including Christ, his most mischievous invention."
- The Social Expert: Julian is adept at impressing everyone at his court with his interactions, being able to act as wise and eloquent philosopher-emperor to his more scholastically inclined courtiers one minute, and to act as the amiable, fierce warrior-emperor to his generals the next. This is in contrast to Constantius.
- The Sociopath: Gallus hits almost every characteristic, fitting for a person who becomes The Caligula.
- Take Over the World: For all his philosophy, Julian ends his memoir giddy with dreams of Persia and India and China. He recounts all the other emperors who measured themselves against Alexander:Each of my predecessors longed to equal this dead boy. None did. Now I shall!
- Teeth-Clenched Teamwork: One of the more entertaining sides of Julian is a scathing letter exchange between Libanius and his collaborator Priscus, who is busy covering his posterior (and his wallet).
- Unfriendly Fire: Julian is killed by one of his own soldiers, who makes it appear as if he was felled by an enemy Persian's spear.
- Unreliable Narrator: Julian's deference to the facts of his own life are spotty. His transcribers step in from time to time to fix any inconsistencies, though they note that Julian is mostly accurate and a fair writer.
- We ARE Struggling Together: The Christians oppose Julian, while constantly killing each other such weighty questions as "Is the Son of the same substance as the Father, or merely similar?"
- Wham Shot!: Priscus pulling out the spearhead from Julian's corpse. A Roman spear.