Caligula: The Immoral Legacy of ‘Little Boots’

Right part of a plaque from the Altar of Domitius Ahenobarbus known as the “Census frieze”. Marble, Roman artwork of the late 2nd century BC. From the Campo Marzio, Rome. / Public Domain

The Roman historian Suetonius referred to Caligula as a “monster,” and the surviving sources are universal in their condemnation.

Edited by Matthew A. McIntosh
Public Historian
Brewminate Editor-in-Chief


Gaius Julius Caesar Augustus Germanicus (August 31, 12 – January 24, 41 C.E.), most commonly known as Caligula, was the third Roman Emperor and a member of the Julio-Claudian dynasty, ruling from 37 C.E. to 41 C.E. Known for his extreme extravagance, eccentricity, depravity and cruelty, he is remembered as a despot, and as the first of the so-called Mad Emperors (contrasted with the Good Emperors.) He was assassinated in 41 by several of his own guards.

The Roman historian Suetonius referred to Caligula as a “monster,” and the surviving sources are universal in their condemnation. One popular tale, often cited as an example of his insanity and tyranny, is that Caligula appointed his favorite horse, Incitatus, to a seat on the senate and attempted to appoint it to the position of consul. The story, however, owes its unrelenting currency to its charm: it is based on a single misunderstood near-contemporary reference, in which Suetonius merely repeats an unattributed rumor that Caligula was thinking about doing it[1]Caligula is often alleged to have had incestuous relationships with his sisters, most notably his younger sister Drusilla, but there is no credible evidence to support such claims either. In short, the surviving sources are filled with anecdotes of Caligula’s cruelty and insanity rather than an actual account of his reign, making any reconstruction of his time as Princeps nearly impossible.

Roman caliga / Munich Archaeological Museum

What does survive is the picture of a depraved, hedonistic ruler, an image that has made Caligula one of the most widely recognizable, if poorly documented, of all the Roman Emperors; the name “Caligula” itself has become synonymous with wanton hedonism, cruelty, tyranny, and insanity. Raised in luxury, with the expectation of exercising enormous power, Caligula may have been as much a victim of circumstance as the cause of his indulgent life and lax morality. He ruled at a time of transition, from the old republican system towards the Emperor exercising more and more power[2] His rule cannot be regarded as setting an example, and his morality is obviously no model. Perhaps his life warns us that too much power and too much wealth corrupts, as suggested by Barrett (1998). He thought himself ‘divine’. Barrett suggests that Caligula saw the Principate ‘as expression of his right to exercise unchecked powers,’ whereas ‘principled Romans would have recognized something sinister in a man who was so lacking in moral scruples that sending fellow humans to their deaths was looked upon not as cruel yet inevitable necessity of governing, but as a matter of almost total indifference’ (241). He ‘manifested a totally self-centered view of the world’ (240).

Early Life

Caligula was born as Gaius Julius Caesar Germanicus on August 31, 12, at the resort of Antium, the third of six surviving children born to Augustus’s adopted grandson, Germanicus, and Augustus’s granddaughter, Agrippina the Elder. Germanicus (Caligula’s father) was son to Nero Claudius Drusus and Antonia Minor. He was nephew to Claudius (the future emperor). Agrippina was daughter to Marcus Vipsanius Agrippa and Julia the Elder. They had four other sons (Tiberius and Gaius Julius, who died young; Nero, Drusus), and three daughters (Julia Livilla, Drusilla and Agrippina the younger).

Gaius’ life started out promisingly, as he was the son of extremely famous parents. His father, Germanicus was a grandson to Tiberius Claudius Nero and Livia, Augustus’s second wife, as well as an adoptive grandson of Augustus himself. He was thus a prominent member of the Julio-Claudian dynasty and was revered as son of the most beloved general of the Roman Empire. Agrippina was herself a granddaughter of Augustus and Scribonia. She was considered a model of the perfect Roman woman.

As a boy of just two or three, he accompanied his parents on military campaigns in the north of Germania and became the mascot of his father’s army. The soldiers were amused whenever Agrippina would put a miniature soldier costume on young Gaius, and he was soon given his nickname Caligula, meaning “Little (Soldier’s) boots,” after the small boots he wore as part of his costume [3]. He would end up hating this name, but he also hated the name “Gaius.”

The question of succession had arisen several times during the life of Augustus, leading to accusations of intrigue within the family. Calicular’s father, Germanicus, was believed by many to have been Augustus’s preferred successor, though at the time of Augustus’s death he was too young to assume the office of Princeps. As a result, Augustus had promoted Tiberius, with the caveat that Tiberius in turn adopt Germanicus. After a successful campaign in Germany and a Triumph in Rome, Germanicus was sent east to distance him from Roman politics, and died on October 10, 19 C.E., claiming to have been poisoned by agents of Tiberius. Relations between his mother and Tiberius deteriorated rapidly amid accusations of murder and conspiracy. The adolescent Caligula was sent to live first with his great-grandmother, and Tiberius’s mother, Livia in 27 C.E., possibly as a hostage. Following Livia’s falling-out with Tiberius and her death two years later, he was returned to his Julian relatives and remanded to his grandmother Antonia. During this period Caligula had little outside contact, and his sole companions were his three sisters, Agrippina the Younger, Drusilla, and Julia Livilla. Later, Caligula’s accusers would focus on this close relationship, accusing the Emperor of having engaged in incest with all three, but especially Drusilla. Suetonius in particular writes a great deal about these supposed acts.

In 31 C.E., Caligula was remanded to the personal care of Tiberius on Capri. He remained there until Tiberius’ death, and his own succession to the Principate in 37 C.E. By this time, Caligula was already in favor with Tiberius. Suetonius writes of extreme perversions happening on Capri, as Tiberius was without the people who managed to keep him in line (Augustus, Livia, his brother Drusus, and his best friend Nerva), so he felt free to indulge in any perversion he desired. Whether this is true or not is hard to say. Unpopular emperors such as Tiberius and Caligula may not have had the whole truth written about them, and gossip is common throughout ancient texts.

At this time, Tiberius’s Praetorian Prefect, Sejanus, was extremely powerful in Rome, and began forming his own alliances against Tiberius’s rule and his possible successors, attempting to court the supporters of the Julian line. Treason trials were commonly practiced, as Tiberius in his old age was growing increasingly paranoid and began to rely increasingly upon his friend Sejanus, who once saved his life. These trials were the main lever Sejanus used to strengthen his position and dispose of any opposition.

From a very early age Caligula learned to tread very carefully. According to both Tacitus and Suetonius, he surpassed his brothers in intelligence, and was an excellent natural actor, realizing the danger when other members of his family could not. Caligula survived when most of the other potential candidates to the throne were destroyed. His mother Agrippina was banished to the tiny island of Pandataria, where she starved herself to death. His two oldest brothers, Nero and Drusus, also died. Nero was banished to the island of Ponza, while Drusus’ body was found locked in a dungeon with stuffing from his mattress in his mouth to keep off the hunger pangs.

Suetonius writes of Caligula’s servile nature towards Tiberius, and his indifferent nature towards his dead mother and brothers. By his own account, Caligula mentioned years later that this servility was a sham in order to stay alive, and on more than one occasion he very nearly killed Tiberius when his anger overwhelmed him. An observer said of Caligula: “Never was there a better servant or a worse master!” Caligula proved to have a flair for administration and won further favor with the ailing Tiberius by carrying out many of his duties for him. At night, Caligula would inflict torture on slaves and watch bloody gladiatorial games with glee. In 33 C.E., Tiberius gave Caligula the position of honorary czarship, the only form of public service Caligula would hold until his reign.

Early Reign

Bust of Caligula / Louvre Museum, Wikimedia Commons

When Tiberius died on March 16, 37, his estate and the titles of the Principate were left to Caligula and Tiberius’s own son, Tiberius Gemellus, who were to serve as joint heirs. Suetonius writes that the Prefect of the Praetorian Guard Naevius Sutorius Macro smothered Tiberius with a pillow to hasten Caligula’s accession, much to the joy of the Roman people. Backed by Macro, Caligula had Tiberius’s will with regards to Tiberius Gemellus declared null and void on grounds of insanity, but otherwise carried out Tiberius’s wishes. Caligula accepted the powers of the Principate as conferred by the Roman Senate, and entered Rome on March 28 amid a crowd that hailed him as “our baby” and “our star.”

His first acts were generous in spirit, though more than likely political in nature. He granted bonuses to the Praetorian Guards, destroyed Tiberius’s treason papers, declared that treason trials were a thing of the past, recalled exiles, and helped those who had been harmed by the Imperial tax system.

Caligula was loved by many simply by being the beloved son of the popular Germanicus. Moreover, he was, unlike Tiberius, a direct blood descendant of Augustus, and therefore related to Julius Caesar. He was also a great-grandson of Mark Antony.

On becoming Emperor, Caligula performed a spectacular stunt. He ordered a temporary floating bridge to be built using ships as pontoons, stretching for over two miles from the resort of Baiae to the neighboring port of Puteoli. He then proceeded to ride Incitatus across, wearing the breastplate of Alexander the Great. This act was in defiance of Tiberius’s soothsayer Thrasyllus prediction that he had “no more chance of becoming Emperor than of riding a horse across the Gulf of Baiae.”

However, following this auspicious start to his reign, Caligula fell seriously ill in October of 37 C.E., and, as Scullard remarks, “emerged as a monster of lust and diabolical cruelty.”

There is some debate as to the chronology here. Authors Michael Grant (1975)[4] and Donna W. Hurley (1993)[5] state that the real break between Caligula and the Senate, and thereafter his extravagant behavior, did not occur until 39 C.E. Though the exact cause of the argument between the young Caesar and the Senate is unclear, what sources remain seem to indicate that the Emperor had demanded a triumph and had been refused by the Senate. What is clear is that in 39 Caligula removed and replaced the Consuls without consulting the Senate, and publicly humiliated several Senators by forcing them to run alongside his chariot in their full robes. It is from this point on that there is a marked change in the biography of his life; the young man previously hailed as “our star” and “our baby” by the Roman people became a despotic tyrant.

Caligula and the Empire

Map of the Roman Empire and neighboring states during the reign of Gaius Caligula (37–41 CE) / Wikimedia Commons

During his short reign, Mauretania was annexed and reorganized into two provinces, Herod Agrippa was appointed to a kingdom in Judaea, and severe riots took place in Alexandria between Jews and Greeks. Though certainly of note, these events are largely ignored by the surviving sources, all of whom unanimously focus on the Emperor as a mentally unstable, homicidal and depraved madman.

Examples of his insanity focus on a handful of episodes in his life, notably Caligula’s military activities on the northern frontier, and his religious policy. His northern campaigns are derided, with accounts of Gauls dressed up as Germans at his triumph, and Roman troops ordered to collect sea-shells as “spoils of the sea” and indicative of his victory against Neptune. Numerous theories and suggestions have been put forth to attempt to explain these actions as anything other than those of a mad-man, the most reasonable suggestion being that Caligula went north to invade Britain and win where even Julius Caesar had been forced to retreat. His troops seem to have had a different campaign in mind, and upon arriving at the shores of the British Channel, the troops refused to go further, hence Caligula ordered them to collect sea-shells as their reward for the “campaign” that they refused to embark upon. Once again, however, due to the lack of sources, what precisely occurred and why is a matter of debate even among the primary sources for Caligula’s reign.

Caligula’s religious policy was a firm departure from the policy of his predecessors. Under Augustus, the Cult of the Deified Emperor had been established and promoted, especially in the western empire, and was generally the first organization established in any new Roman colony. Augustus proclaimed on multiple occasions that he was not himself personally divine; instead the Cult centered around his numen, his personal spirit, and gens, the collective spirit of his family and ancestors. After Augustus, Tiberius seems to have had little interest in the Cult, and its promulgation and expansion seems to have been on a local level and driven by local magistrates, rather than from a central organizational structure. Caligula expanded this Cult on an unprecedented scale. The temple of Castor and Pollux on the Forum was linked directly to the Imperial residence on the Palatine and dedicated to Caligula himself; he would appear here on occasions, dressed and presenting himself as a god, and demanding that those in his presence adopt sycophantic methods of acknowledging him. The nature of the Cult of the Deified Emperor changed from honoring the spirits around the Emperor to direct worship of Caligula himself. Likewise, Caligula’s policies affected religious practice in the whole of the Empire, not just those practices associated with the Cult. The heads of the statues of many of the gods throughout Rome and the empire were replaced with Caligula’s head, including many of the female statues, and Caligula demanded that he be worshiped as an embodiment of these gods, similar to the Hellenistic ruler-cults. Caligula even planned to place a statue of himself as Zeus in the Holy of Holies in the Jewish Temple in Jerusalem; the Jews had been granted religious rights and freedom by Julius Caesar, and were generally treated as being outside the scope of Roman religious law. This attempted was delayed for years by the governor, Publius Petronius, and finally ended due to the intervention of Herod Agrippa, a personal friend of the Emperor and king of Judea.

Downward Spiral

An equestrian statue of a Julio-Claudian prince, originally identified as Caligula. / British Museum

Outlandish stories cluster about the raving emperor, illustrating his excessive cruelty, multiple and peculiar sexual escapades (both heterosexual and homosexual, at least as claimed by Suetonius,[6], or disrespect toward tradition and the Senate.

The sources describe his incestuous relations with his sisters, his disembowelment of his sister (to get to the child he impregnated her with), his selling to the highest bidder of the wives of high ranking Senate members during sexual orgies, his laughable military campaigns in the north, the plan to make Incitatus a consul, and his habit of roaming the halls of his palace at night ordering the sun to rise.

He comes across as aloof, arrogant, egotistical, and cuttingly witty, and is generally portrayed as insane. He is said to have cried “I wish the Roman people had but a single neck” when an arena crowd applauded a faction he opposed. Suetonius wrote that he often uttered “Let them hate, so long as they fear,” and described this as a familiar line of the tragic poet (Accius); however, Suetonius also attributes the utterance of this line to Tiberius. Whatever else may be said about Caligula and his reign, it is known that his rule was short and tumultuous, and that after his death there were few who mourned his passing.

Caligula was also incredibly self-indulgent, dramatic proof of this has been found with the discovery of two sunken ships at the bottom of Lake Nemi. These two ships were by far the largest vessels in the ancient world, in fact their size was not even rivaled until after the Renaissance. The smaller of the ships was designed as a temple that was dedicated to Diana (the Roman equivalent of Artemis), the larger ship however was essentially an elaborate floating palace, which counted marble floors and plumbing among its amenities, the sole role of which was to satisfy Caligula’s increasingly hedonistic behavior.


The assassination of Caligula, by Lawrence Alma-Tadema / Walters Art Museum, Wikimedia Commons

Caligula was murdered following a conspiracy amongst officers of the Praetorian Guard, apparently for reasons of personal insult and spite. Some have suggested the plot was more extensive than the sources indicate, including many senators, imperial freedmen, and even the support of the next emperor Claudius, but there is little if any evidence to support such claims, although Josephus ‘reflects a tradition’ that Claudiu’s’ ‘rise to power’ came ‘about through a cohesive plot’ [7]. Barrett points out that Claudius was well aware that he owed his promotion to Chaerea ‘but saw the danger in the precedent of regicide’, and more or less persuaded the Senate, which had heaped praise on Chaerea, to condemn him. He was ‘forced to commit suicide’. No action was ever brought against Sabrinus, although he also committed suicide. Had Claudius known of a plot, he would anyway have ‘been anxious to prevent any general knowledge of it afterwards’ to ‘foster the notion that the principate came to him by an accidental twist of fate’ (177).

What is known is that on January 24, 41, the praetorian tribune Cassius Chaerea and other guardsmen accosted Caligula while he was addressing an acting troupe of young men during a series of games held for the Divine Augustus. Chaerea had a distinguished record as one of Germanicus’s best officers and had known Caligula since infancy. One possible motive provided by Suetonius is that Chaerea had experienced years of abuse by Caligula over his so-called effeminacy, possibly due to a wound to his genitalia; Suetonius records that Caligula commonly gave the watchwords “Priapus” (erection) or “Venus” (Roman slang for a eunuch) when Chaerea was on duty. Chaerea requested the watchword from the Emperor and, after Caligula’s response, struck the first blow. The co-conspirators quickly moved in and stabbed the Emperor to death, according to Josephus’s account only a few feet away from his guard and entourage. By the time Caligula’s German guard responded in a rage by attacking the co-conspirators and innocent civilians alike, the Emperor was already dead. It is believed that the final blow was in Caligula’s genitalia, delivered by Chaerea. Chaerea and another aggrieved tribune, Cornelius Sabinus, also killed Caligula’s wife Caesonia and their infant daughter, Julia Drusilla, by smashing her head against a wall.

Caligula’s Insanity

Recent sources say that Caligula probably had encephalitis. Ancient sources, like Roman biographers Suetonius and Cassius Dio, describe Caligula having a “brain fever.” Philo of Alexandria reports it was nothing more than a nervous breakdown, as Caligula was not used to the pressures of constant attention after being out of the public eye for most of his life. Rome waited in horror, praying that their beloved Emperor would recover. He became better, but his reign took a sharp turn. The death of Gemellus and of Silanus, Caligula’s father-in-law, took place right after Caligula recovered.

The question of whether or not Caligula was insane remains unanswered. Philo, author of Legatio ad Caium (“embassy to Caius”) and leader of a delegation sent to Caligula to seek relief from persecution by Alexandrian Greeks, claimed that the emperor was no more than a vicious jokester. Based on the contemporary reports of his behavior, modern psychology would likely diagnose Caligula as delusional, and possibly suffering from antisocial personality disorder as a result of his traumatic upbringing.

However, given Caligula’s unpopularity as emperor, it is difficult to separate fact from fiction. There are many famous stories attesting to his bizarre behavior as emperor: that he tried to make his beloved stallion, Incitatus, a consul, though this could have been a political statement indicating that he felt his horse was as well qualified for the position as any of the incumbents. Other stories claim that there existed incestuous relationship between Caligula and his sisters (particularly Drusilla), a brothel he set up at the palace featuring the wives of prominent senators, his abandonment of a campaign in Britain that instead resulted in his soldiers collecting seashells as “spoils of the sea” in his battle with the sea god Neptune, wanting to erect a statue of himself in Jerusalem (his good friend Herod Agrippa stopped it), his amusement with shutting down the granaries and starving the citizens, his hobby of watching executions as he ate, and labeling himself a “god.” According to Suetonius he “often sent for men whom he had secretly killed, as though they were still alive, and remark off-handedly a few days later that they must have committed suicide.” Regardless of the validity of any of these anecdotes, historians tend to agree on one fact, that Caligula was extremely unqualified and unprepared to be Emperor.

Alternate Views

Bust of Caligula / Ny Carlsberg Glyptotek, Wikimedia Commons

The lack of a full accounting of Caligula’s reign, and the hyperbolic nature of the records that do remain, creates several problems for historical analysis. It must be noted that, except for Philo’s Embassy to Caius and mention by Josephus’ Antiquities of the Jews,Chapters 6 through 8, all historical writings regarding Caligula are authored by Romans of Senatorial rank; a class of individuals whose power had been severely checked by the growth of the Principate. Additionally, in Roman politics sexual perversity was often presented hand in hand with poor government; Suetonius accuses Augustus, Tiberius, Caligula, and Nero all of sexually perverse behavior, and also heavily criticizes many of the administrative aspects of these Emperor’s rules. Therefore, much of what is recorded about Caligula, especially that coming from Suetonius, must be taken “with a grain of salt.”

It is known that in 39 C.E. there was a political break between Caligula and the Senate, and it is from this point forward that Caligula’s reign takes on a decidedly despotic tone. The purges of Tiberius had removed from the Senate some of the staunchest supporters of the Julian line, of which Caligula was a prominent member. Caligula was thus presented with a Senate that, at best, offered half-hearted support. Additionally, the absence of Tiberius for much of his reign meant that the Senate, previously docile after almost 50 years under Augustus, had been forced to take up much of the administrative apparatus of the Empire once again. Caligula was thus faced with an uncooperative Senate that was once again beginning to rule the Empire as it had before Caesar and Augustus.

The position of the Princeps was an elaborate facade that required the most powerful man in Rome to act as if he were nothing more than a concerned citizen and magistrate under the Senate’s supervision. Caligula, faced with an uncooperative Senate, seems to have quickly tired of this facade and decided to act indiscriminately with the powers given to him as Princeps. The vast financial reserves that Tiberius had left behind were quickly spent and the imperial treasury emptied by the end of Caligula’s brief reign. Caligula’s reign saw the expansion of the imperial court and imperial palace into the Forum itself. Imperial duties and responsibilities that Tiberius had returned to the Senate were reclaimed as rights of the Princeps, and the powers of the Senate were further restricted. Perhaps modeling his rule after the Hellenistic monarchs, Caligula sought to make himself the center of all religious activity, as has been noted above.

In essence, Caligula sought to take the Principate to its next logical step: a divine monarchy. However, the complexities of Roman society and Roman politics demanded that the facade of the “first-citizen” be continued. Suetonius compares Caligula to Julius Caesar; in the mind of the Roman Senate, the delicately balanced Principate had become little more than the tyranny it had rid itself of a century before. Thus, much of the sensational accusations leveled at Caligula could be viewed as politically motivated attacks against his character and his memory. It must be kept in mind that the records that we have today of Caligula were all written by his political opponents, and those most damaged by his attempt to enforce his absolute authority.



  1. (Suet. Cal. 55.3). Suetonius, The Lives of the Caesars
  2. Technically, there never was an official title, Emperor. The term Imperator was used, which really means commander in chief. The name ‘Caesar’ came to serve as the title of the first citizen. Caligula’s title was always Princeps, or first citizen, which had to be ratified by the Senate.
  3. “Caligula” is formed from the Latin word collage, meaning soldier’s boot, and the diminutive infix -UL.
  4. Michael Grant. The Twelve Caesars. (New York: Charles Scribner’s Sons, 1975)
  5. Donna W. Hurley. An Historical and Historiographical Commentary on Suetonius’ “Life of C. Caligula”. (Atlanta, GA: Scholars Press, 1993)
  6. Suetonius, The Lives of the Caesars. Cal. 36) Retrieved September 18, 2008.
  7. Anthony Barrett. Caligula: the corruption of power. (New Haven: Yale University Press, 1989), 176


  • Barrett, Anthony. Caligula: the corruption of power. New Haven: Yale University Press, 1990
  • Ludwig Quidde’s essay Caligula. Eine Studie über römischen Caesarenwahnsinn (Caligula: A Study of Imperial Insanity) (1894), in which Caligula is likened to the German Emperor Wilhelm II.
  • Caligula is the title of a play by Albert Camus, which was the basis for a 1996 Hungarian movie and the 2001 made for TV version.
  • Grant, Michael, The Twelve Caesars. New York: Charles Scribner’s Sons, 1975
  • Hurley, Donna W. An Historical and Historiographical Commentary on Suetonius’ “Life of C. Caligula”. Atlanta, Geogia: Scholars Press, 1993

Originally published by New World Encyclopedia, 01.05.2017, under a Creative Commons Attribution-ShareAlike 3.0 Unported license.