Riordan Wiki

I told you this isn’t a game! You don’t walk away from me alive!

–Caligula to Jason Grace in The Burning Maze.

Gaius Julius Caesar Augustus Germanicus, better known as Caligula, was a Roman Emperor who was made a god-emperor by his followers. He was the main antagonist in The Burning Maze and a supporting antagonist in The Tyrant's Tomb. He was a Triumvirate Holdings leader alongside Nero and Commodus. He was killed in an explosion caused by Frank Zhang during the Battle of San Francisco Bay.


Early Life

Gaius Julius Caesar Augustus Germanicus was born on the day before the Kalends of September in the year 12 AD under the consulship of his father Germanicus and Gaius Fonteius Capito. His mother was Agrippina, the granddaughter of the first emperor, Augustus. By the age of three, he began accompanying his father Germanicus on the general's military campaigns. He received the cognomen "Caligula" jestingly from the legionaries, for he was raised amongst them and dressed in the garments of a soldier, including in a type of footwear called caligae. Furthermore, it is well known how much he thrived in their love and graces by this manner of edification, especially when after the death of Augustus, as they became seditious and rushed headfirst into madness, they were stilled by the sight of him alone.

During his youth, he received a prophecy from Tiberius' soothsayer, a Roman astrologer named Thrasyllus, who told him he had as much chance of becoming emperor as he did of riding a horse across the Bay of Baiae, meaning it was impossible.

Death of Father and Becoming Emperor

Caligula's father later died while on a campaign in Syria, on which he had accompanied him; the rumor was that it was by the treachery of Tiberius, under the supervision and aid of Gnaeus Piso, who at that same time was governor of Syria, and who, believing it necessary to find fault with the father and the son as if it were plainly the only thing to be done, had assailed Germanicus with bitterness and harshest of words and deeds, even when the general was ill. Whence returning Caligula first lived with his mother, then, with her being banished he stayed in the home of his great-grandmother Livia. After she perished, he went to his grandmother Antonia, and at nineteen years of age he was summoned to Capreae by Tiberius. On that same day, he accepted the toga of manhood, although without ceremony.

Here, although he was prodded by all sorts of trickery of those attempting to entice him or drive him to complaint, he never allowed them, ignoring the destruction of his family as if nothing had befallen to anyone. Still, he could not keep in check his cruel and vicious nature, in that he would attend most eagerly the chastisement and torturing of those who were to be punished, frequent cheap dining houses and brothels and night while disguised under a wig and long cloak, and lustfully seek scenes of dancing and singing; Tiberius was very patient with him, if only in order tame his fierce nature.

Not long after, he married Junia Claudilla, the daughter of the well-known nobleman Marcus Silanus. Since the court was vacant and Sejanus, a close friend to Tiberius, was suspected of being an enemy and thus removed, he was impelled little by little to the hope of being successor. In order to strengthen it, after Junia was lost in childbirth, he began to seduce Ennia Naevia, the wife of Macro, who then was a prefect of the praetorian cohorts, and promised their marriage if he obtained the empire. Having become friends with Macro through her, he either killed Tiberius with poison, as some say, and then ordered a pillow to be thrown over his face as he resisted or even suffocated him with his own hand.

Thus he obtained power over the empire.

Life as Emperor

After he had entered the city, he was immediately given the right and sway over all things by a consensus of the Senate and of the crowd which was trying to break into the Senate-house, with Tiberius' will made vain, who in his testament had declared his other grandson to be co-heir. The people's happiness was so great that in the next three months approximately one hundred and sixty thousand animals are said to have been sacrificed. A few days later, after he had reached the islands nearest to Campania, prayers were made for his return. However, he soon fell ill, and during this time there were some that said they would fight or be killed themselves if but he could be healthy. There were also many foreigners who favored him in addition to the love of his citizens. While ill, he recalled many of those who had been banished by Tiberius, released many from whatever former charges they were accused of, and completed several unfinished projects, instituting a great number of games as well. During this time he was called "Pious", "Son of the Camp", "Father of Armies", and "The Best and Greatest Caesar".

Yet soon, he began to join to himself a kind of divine majesty. He ordered that statues of gods either famous for their art or piety be brought from Greece, and after cutting off their heads he would place an image of his own upon them. Then he extended a part of his Palace to the forum, and with the temple of Castor and Pollux being transformed into its vestibule, he would often stand between the two gods, showing himself off as a deity to the passersby. He erected a temple for the worship of his own divinity and established his own priesthood and sacrifices. In the temple there stood a gold likeness of himself which was clothed every day in the clothes that he wore. He had both his grandmother and his brother killed as well. With all his sisters he made a habit of incest, one of whom he made heir to his property and to the empire. When she died he instituted a public mourning, in which bathing, laughing, and dining with one's parents, spouse, or children was a capital offense.

He became irreverent and unmerciful towards the Senate. He made some of the senators who had achieved the highest honors run beside his chariot for great distances while wearing togas, and wait on him with napkins at his meals. Others, even though he had killed them in secret, he would continue to summon as if they were still alive, and after a few days he would claim that they had died by suicide. He also removed the consuls that forgot to celebrate his birthday. When the price of animals for gladiatorial games rose, he would select criminals to be torn apart, and those who had sworn they would either fight or perish for him were forced to fulfill their oaths. He forced parents to attend their children's executions, after which he invited them to dinner in jest. He also did not allow anyone to be put to death except by the infliction of many small wounds, telling the executioners to "strike so that he feels he is dying".

A phrase that he often repeated was: "Let them hate me, as long as they fear me".

There was a party on the level of those for the Super Bowl; even Apollo and some other gods disguised themselves to join. At the party Caligula exhibited his usual cruelty; this included having the tongue of a poet who wrote a satire about him pulled out, dipped in silver and displayed for all to see, and enslaving a senator after the man agreed to be his slave, believing that the emperor was commenting on his slave disguise. When he noticed Apollo dressed as a gladiator, the disguised god managed to amuse the emperor and earn a reward by playfully stabbing one of his praetorian guard with a fake tin blade and swearing to protect him.[1]


On January 24 in the year 41 AD, at around one o'clock in the afternoon, although unsure of whether he should rise and eat lunch, for his stomach being still full with the previous day's meal, he left his home at the persuasion of his friends. When in an underground tunnel, through which the path lay, famous actors summoned thither from Asia were being prepared to act a play, he suddenly halted in order to inspect them and to encourage them. Had the leader of the group not complained to be cold, he would have immediately returned and had the spectacle begin. Hereafter there are two versions of what happened: some say that Cassius Chaerea, a Roman soldier, struck him from behind in the neck with the edge of his gladius, as he was speaking with the actors, crying out "take this!", after which Cornelius Sabinus, a tribune and another of the conspirators, impaled his chest from the front. Some say that, after the crowd had been removed by the centurions who were in on the plot, Sabinus, in the manner of a soldier, sought the signal, and so when Caligula uttered "Jupiter", he said "take thus your doom!", and as the emperor glanced back he clove his jawbone with his sword. As Caligula lay upon the ground drawing in his limbs and crying out that he still lived, the rest killed him with thirty wounds, for all were raising the cry: "Again! Again!"

He was reborn as a god. His uncle, Claudius, was declared the new emperor by the praetorian guard.

In the Series

Caligula, alongside Nero and Commodus, influenced many events throughout history via Triumvirate Holdings -- using the company to fund Luke Castellan during the Second Titan War, and Octavian during the Second Giant War. At some point in time, he bought fifty super-yachts and used them all as a palace sailing near California, each was named after Julia Drusilla. He managed to capture Herophile, the oracle of Erythaea, and lock her into the Labyrinth inside a room filled with lava only available to those wearing his adult-sized caligae. He recruited Medea to help gain the faded essence of her grandfather, Helios, so he can become the new sun god. Caligula also called Naevius Sutorius Macro and Incitatus back to life. The emperor originally had Automatons replace praetorian guards, but since they malfunctioned so many times he exiled them to Palm Springs with Macro, they were replaced by human mercenaries, Strixes and Pandai.

Using his N.H. Financials, a division of the triumvirate, Caligula spent years and tens of millions of dollars filing many legal papers against Tristan McLean, the famous film star, to destroy his credit, assets, and reputation with the studios. McLean's former personal assistant, Jane, was in on the plan along with his financial manager, accountant and film agent. He and his daughter, Piper McLean, lost everything except their house Tahlequah, Oklahoma, the one in Malibu was getting repossessed with all things inside being taken to the Triumvirate.

The Heroes of Olympus

The House of Hades

Hazel Levesque mentions him and Nero when Jason is talking about Diocletian, she says that the nuns at St. Agnes Academy for Colored Children and Indians told them that the emperors were malicious for slaughtering Christians ruthlessly.

The Kane Chronicles

The Throne of Fire

While leading Sadie Kane and Walt Stone through the catacombs of Bahariya, Mad Claude tells them about a date farmer who was named Caligula after the emperor. Mad Claude calls it a horrible name, stating that once you're named for an emperor, even a psychotic one, you can't do much about it.

The Trials of Apollo

The Hidden Oracle

Caligula makes a small cameo in the penthouse terrace of the building in New York City with Nero and Commodus. Rachel Elizabeth Dare managed to take a picture of them but couldn't see their faces.

The Dark Prophecy

Meg mentions meeting him once, but does not remember his name. In fact, according to her, even Nero fears him. He, apparently, calls Caligula his "kinsman" as they are related.

The Burning Maze

Before meeting the emperor on Julia Drusilla XII, Apollo dreams of two flashbacks of him. One of them was after Tiberius was killed and the other was when the palace at Palatine Hill was open.

Caligula greeted Apollo and Piper after they are taken to his throne room by Incitatus. He taunted Apollo and ordered the Pandai, as they subdued, to be executed. Just as he ordered Meg and Jason to be eliminated, he became stunned when Apollo proposed a suicide threat because Medea confirmed that Caligula wouldn't be able to become the sun god if Apollo was already dead. Moments later, a Pandos messenger named Flange informs him that the attack on Camp Jupiter that night has failed and the emperor kills him with his own sword. He tells his guards to sail north, Apollo uses this opportunity to stab himself. Medea tells Caligula that they must perform the ritual before Apollo dies. Unknown to them, the tornado prisons start to weaken. He fights Jason, who was riding Tempest the Storm Spirit, on Incitatus and manages to defeat and kill the son of Jupiter using numerous arrows and his spear. In the end of the fight, he stabbed Jason between his shoulder blades with his spear once again to make sure that he is dead. After the heroes flee, he sails north to the Bay Area.

Unfortunately for him, Medea was killed and the essence of Helios was returned to Chaos, therefore he did not become the new sun god. Incitatus was going to catch up to Caligula after telling the heroes where he was going, but he was killed by the Meliai.

The Tyrant's Tomb

Caligula and Commodus are seen in a dream sailing north to continue to assault on Camp Jupiter, discussing battle plans and their disdain for Nero. He is upset when he learns they will reach the camp in a week, hoping to reach the camp by the blood moon in five days.

When they test their Greek Fire cannons he is pleased with the results and Commodus reminds him to try and take Tyson and Ella alive if they can.

During the second wave of the assault, he and Commodus pull up to the Caldecott Tunnel and demand surrender, but Frank Zhang calls spolia opima, single combat to the death, and they accept. When Apollo arrives he joins the fight. He fights the son of Mars as Commodus fights Apollo. He and the praetor enter the tunnel and take careful strikes at one another. Frank turns into a swift and takes out one of his eyes, however he swats the son of Mars against the wall and he reverts to human form. He stabs Frank in the back but his cloak protects him. The praetor ignites his stick, covering them both in flames and creating a massive explosion from the trap Frank set before. Apollo senses that his life force has left the land of the living finally avenging Jason.


Caligula is considered one of the most (if not the most) malevolent Roman emperors in history. Indeed, he is so cruel and ruthless, that even his nephew Nero is said to fear him. Caligula shows little to no concern at all to his subordinates, regularly ordering the execution of anyone who displeases or fails him, Incitatus being the only exception, as he is the only follower whom the god-emperor views as an equal. He also kills any subordinates whom angers him whether it is be with bad news or other things.

Caligula is also extremely power-hungry, always seeking to achieve more power. Back to his reign as emperor, he would disguise himself as several major Olympian gods, such as Mars, Jupiter, or Apollo, and he even gave himself the alias "Neo Helios", which meant "New Sun". His hunger for power made Caligula the first Roman emperor to ever try to become a living god, as he plans to absorb the power of Helios and Apollo in order to become the new god of the sun. Additionally, Caligula is extremely confident, showing no fear that the gods' wrath may fall upon him, even after he profaned a sacred temple of Castor and Pollux, and started to compare himself to the gods. In fact, Caligula has so much confidence, that even Apollo himself became intimidated by him. Caligula was also notorious for his pleasure barges that included huge floating palaces with bathhouses, theatres, rotating statues, racetracks, and thousands of slaves. Despite owning super-yachts, Caligula can't swim, but that didn't faze him.

Much unlike Commodus, Caligula is surprisingly patient, as he waited years for his uncle Tiberius to die until finally ordering him to be assassinated. He said he doesn't play games like him, he goes right for the kill, Commodus is more interested in a good spectacle. When confronting Apollo, instead of killing him and consuming his essence immediately, decided to instead take his time taunting Apollo and torturing Jason, Meg and Piper. When Flange came in with an urgent message, Caligula was at first willing to wait and hear the message later, until the pandos insisted that his message was of the utmost importance. However, Caligula's patience does have limits, as he grew tired of waiting for Tiberius to die, and demanded him to be murdered instantly.

Caligula’s super yachts are all named after his favorite sister, Julia Drusilla. This shows that Caligula may feel some remorse for his deceased sister.


Caligula was young, slender and lithe. He was handsome in a thin angular way, though his ears stuck out a bit too much and were too prominent. His smile was twisted and too thin, and his placid brown eyes that were too far apart had "all the warmth of a barracuda's".

In Apollo's first dream, after Macro killed Tiberius, Caligula wore white robes and sandals. In Apollo's second dream, when Caligula pretended to be him, he was butt naked, painted in gold from head to foot, with a spiky crown of sun rays across his brow.

When the heroes encountered him on his Julia Drusilla XII yacht, Caligula was dressed in white slacks, white boat shoes, a striped blue-and-white shirt, a blue blazer, and a captain's hat. With Medea, it made him look like Daryl Dragon of Captain & Tennille.


As a God-Emperor, Caligula can be assumed to be a considerably powerful being compared to mortals and demigods. However, he is stated to only be a minor god in The Tower of Nero, suggesting that in general, he's not very powerful.

  • Immortality: Caligula became immortal after becoming a God-Emperor.
  • Fighting Prowess: Caligula is an exceptionally skilled and experienced fighter, displaying great fighting prowess with his spear, as he proves capable of competing against Jason Grace himself, an extremely skilled demigod on par with Percy Jackson, and even managed to eventually defeat and kill him. However, is worth noting that Jason was also trying to protect his friends, while fighting Caligula at the same time. He would later prove to be more than a match for Frank Zhang, another extremely skilled demigod, nearly killing him in the process.
  • Superhuman Speed: Lunged at Apollo with blinding speed and easily deflected an arrow midair.
  • Superhuman Strength: Caligula struck Piper McLean with enough force to make her spin in a circle before collapsing.
  • Resurrection (Limited): As a God-Emperor, Caligula has shown a limited power of resurrection, calling his followers back to the land of the living to serve him aided by their souls escaping from Erebos.


  • Caligula is the first and so far only major antagonist to successfully kill a main character, in his case Jason Grace. While Gaea did manage to kill Leo Valdez near the end of The Blood of Olympus and Surt killed Magnus Chase early in The Sword of Summer, both were revived soon after and Magnus' later deaths were all within Valhalla where he was also rapidly revived. All other characters killed, such as Zoe Nightshade, Michel Desjardins, or Gunilla, were secondary characters.
  • Caligula believed that people should never accept their lot in life if it was given to you unfairly. That was how he became a god after his assassination and why he tried to replace Apollo
  • Caligula is the second god to die in the series after Harpocrates, and the first to be killed instead of dying of their own accord. The third is Commodus.


  1. The Burning Maze, Ch. 19
The Trials of Apollo
Core Series: The Hidden Oracle | The Dark Prophecy | The Burning Maze | The Tyrant's Tomb | The Tower of Nero
Main Characters: Apollo/Lester Papadopolous | Meg McCaffrey | Percy Jackson | Peaches | Leo Valdez | Calypso | Grover Underwood | Piper McLean | Jason Grace | Reyna Ramírez-Arellano | Frank Zhang | Hazel Levesque | Lavinia Asimov | Nico di Angelo | Will Solace | Rachel Elizabeth Dare
Secondary Characters: Chiron | Austin Lake | Kayla Knowles | Hemithea | Josephine | Georgina | Lityerses | Trophonius | Gleeson Hedge | Mellie | Chuck Hedge | Medea | Herophile | Crest | Don | Tyson | Ella | Tarquin | Luguselwa | Claudia | Janice | Blaise
Minor Characters: Sally Jackson | Thalia Grace | Mrs. O'Leary | Festus | Cade | Mikey | Harley | Connor Stoll | Miranda Gardiner | Cecil Markowitz | Ellis Wakefield | Sherman Yang | Damien White | Malcolm Pace | Paolo Montes | Valentina Diaz | Germani | Agamethus | Olujime | Phillip McCaffrey | Hunter Kowalski | Sssssarah | Prickly Pear | Aloe Vera | Joshua | Naevius Sutorius Macro | Incitatus | Tristan McLean | Bombilo | Aurum | Argentum | Julia | Jacob | Poison Oak | Screech-Bling | Annabeth Chase | Elon | Mamurius Veturius | Mimi
Olympian Gods (Greek & Roman): Zeus/Jupiter | Hera/Juno | Poseidon/Neptune | Demeter/Ceres | Ares/Mars | Athena/Minerva | Apollo/Apollo (Roman) | Artemis/Diana | Hephaestus/Vulcan | Aphrodite/Venus | Hermes/Mercury | Dionysus/Bacchus | Hades/Pluto
Minor Gods: Nero | Commodus | Caligula | Iris | Britomartis | Styx | Terminus | Lupa | Terpsichore | Harpocrates | Cardea
Titans: Rhea | Leto | Mnemosyne | Helios
Monsters and Magical Creatures: Python | Nosoi | Karpoi | Palikos | Myrmekes | Colossus Neronis | Blemmyae | Gryphon | Carthaginian Serpent | Scythian Dracaena | Cynocephali | Centaur | Cyclops | Yale | Satyr/Faun | Strix | Dryad | Dragon | Pandai | Eurynomos | Skeleton Warriors | Vrykolakai | Raven | Khromandae | Amphisbaena | Troglodyte | Tauri Sylvestres
Related Content: Rick Riordan | Percy Jackson and the Olympians | The Heroes of Olympus | Demigods & Magicians | Camp Half-Blood Confidential | Camp Jupiter Classified: A Probatio's Journal | Percy Jackson Demigod Collection | Un Natale Mezzosangue