Biographies & Memoirs


Bust of Caligula. Copenhagen, Ny Carlsberg Glyptotek 637 (Inv. 1453). Photo: Ole Haupt.



Digesta Justiniani


Cassius Dio, Roman History

Jos. Ant.

Flavius Josephus, Antiquitates Judaicae

Phil. Leg.

Philo, Legatio ad Gaium

Sen. Ad Helv.

Seneca, Ad Helviam Matrem de Consolatione

De Const. Sap.

Seneca, De Constantia Sapientis

Suet. Aug.

Suetonius, De Vita Caesarum libri: Augustus


Suetonius, De Vita Caesarum libri: Gaius Caligula


Suetonius, De Vita Caesarum libri: Claudius


Suetonius, De Vita Caesarum libri: Tiberius


Suetonius, De Vita Caesarum libri: Vitellius

Tac. Ann.

Tacitus, Annales


Figure 1. Ruling Emperors.


A Mad Emperor?

Caligula, the man who was Roman emperor from A.D. 37 to 41, started out as a tyrannical ruler and degenerated into a monster. He drank pearls dissolved in vinegar and ate food covered with gold leaf. He forced men and women of high rank to have sex with him, turned part of his palace into a brothel, and even committed incest with his own sisters. The chief victims of his senseless cruelty were Roman senators. Torture and executions were the order of the day. He removed two consuls from office because they had forgotten his birthday. He considered himself superhuman and forced contemporaries to worship him as a god. He wanted to make his horse a consul and planned to move the capital of the Empire from Rome to Alexandria.

His biographer Suetonius, to whom we owe most of this information, and the other ancient sources have an explanation for this 'font-size:12.0pt;font-family:"Times New Roman",serif;color:black'> “insanity.” Pliny the Elder and Flavius Josephus, two authors writing several decades later, mention his absurd behavior and report on his “madness.” At the beginning of the second century Tacitus, the most noted historian of the Roman Empire, whose account of Caligula’s reign has been lost, speaks of the emperor’s “troubled brain.” Suetonius, who wrote his biography a little less than a hundred years after Caligula’s death, considered him to have been “mentally ill,” and Cassius Dio, who wrote a voluminous history of Rome at the start of the third century, also believed that the emperor had “lost his head.”

No wonder, then, that modern scholarship has followed these conclusions: “Imperial madness” is the standard explanation. Ludwig Quidde, who made this term famous at the end of the nineteenth century, describes this “disease” as “megalomania, carried to the point of regarding oneself as divine; disregard for all limits of law and all the rights of other individuals; brutal cruelty without purpose or reason.” Although these elements are also found “in other mentally ill people,” the unique quality of an emperor’s madness lay in his position as ruler, which “provides particularly fertile soil for the seeds of such a predisposition and permits them to develop unhindered in a manner that is otherwise hardly possible.” For Quidde’s contemporaries, however, this brief biographical sketch of Caligula had a double meaning, a hidden intention beneath the surface of the words. They saw the depiction as so clearly aimed simultaneously at another emperor, Kaiser Wilhelm II of Germany—who was certainly not insane—that Quidde’s book ran through thirty printings within a short time. It also earned the author three months in prison and ended his academic career. Yet these events did not weaken the impact of his conclusions about Caligula. The author of a recent biography (published in 1991) still describes the emperor as “crazy,” and a recent survey of the scholarly literature contains references to his “imperial madness.”

Readers of this biography of Caligula thus appear to be in for quite a story—and indeed they are. Matters are considerably more complicated than might appear at first glance, however. It was established during the nineteenth century that ancient accounts of this emperor are by no means as much in agreement as they may seem. Take Caligula’s sex life, for example: The claim that the emperor committed incest with his three sisters is misinformation that surfaces for the first time in Suetonius. Its hollowness is easily proved: The emperor’s two contemporaries Seneca and Philo, who were both familiar with aristocratic circles in Rome and well informed, heap invective on the emperor and would hardly have failed to mention such a charge had it been in circulation then. But clearly they knew nothing about it. The same holds for Tacitus. In his history of the early Empire he discusses at some length the dissolute life of the younger Agrippina, who was Caligula’s sister and the wife of the later emperor Claudius. He even considers her capable of having attempted incest with her own son, the emperor Nero. Clearly he would have mentioned any incest between Agrippina and her brother, which would have suited his account, but no such allegation was known to him. Thus the story was invented at some point after Caligula’s death.

A further example: A broadly based conspiracy against Caligula took place midway through the year 39, in which many members of the Roman aristocracy participated, including an important military commander in Germania, the emperor’s sisters, his closest confidant among the senators, and the sitting consuls. It was a highly dramatic occurrence, which threatened the emperor’s life and fundamentally altered his behavior toward his fellow members of the senatorial order. Curiously, the early sources are completely silent on the matter. Suetonius does not devote a single word to the conspiracy itself; he describes only the emperor’s apparently confused reactions to it. Yet two casual references to it in his biographies of the emperors Claudius and Vespasian reveal that the events, which are also documented in inscriptions, were well known to him.

Many more examples could easily be given, as will become apparent later. They point to the following conclusion: The accounts of Caligula surviving from antiquity pursue the clearly recognizable goal of depicting the emperor as an irrational monster. They provide demonstrably false information to support this picture of him and omit information that could contradict it. They present the emperor’s actions out of context, so that their original significance is either completely obscured or can be grasped only with great difficulty. The authors offer assessments of his behavior that often contradict other information contained in their very own accounts.

And finally on the matter of his insanity: Ancient scholars discussed the phenomena and causes of psychopathology from the fifth century B.C. on. During the reign of the emperor Tiberius, Caligula’s predecessor, the Roman author Cornelius Celsus wrote on this subject in his books on medicine (De Medicina). Celsus characterizes insanity (insania) as a disease that manifests itself in senseless behavior or incomprehensible speech. He describes two categories of patients: those who have delusions but whose intellectual reasoning is otherwise unimpaired, and those whose reason is itself disturbed. Later medical authors who employ the same distinction give as an example of the former a man named Theophilus, who—although he could speak and reason properly otherwise—believed that he was constantly surrounded by people playing flutes, making noises, and observing him. He often upset the household by shouting orders that these interlopers should be thrown out. As an example of the latter ailment the authors describe a patient who suffered from the delusion that he had no head. He believed that he was a beheaded tyrant.

The subject was covered in Roman law as well. A series of texts on homicide, treason (maiestas), libel, and property damage declare that “the insane” (furiosi, insani) are not legally responsible for their actions. “What delinquency . . . can there be in a person who is not in his right mind?” asks the legal scholar Pegasus (Dig.* It is even noted specifically that in the case of crimes committed by someone of unsound mind, it is not the perpetrator himself who deserves punishment, but rather those who failed to keep watch over him.

How should we imagine the situation in the case of Caligula? Do we suppose that there is a Roman emperor who behaves irrationally, whose speech is incomprehensible, whose perceptions of reality are disturbed, and who commits all sorts of crimes in this condition, without anyone’s intervening to stop him? If that had been so then an accusation of insanity would have had to be leveled, not at the emperor, but rather at the society that surrounded him: at the Roman aristocracy first and foremost, meaning the Senate that carried out his decisions, the magistrates in Rome who followed his instructions, and the military commanders and governors in the Empire who obeyed his orders. Blame would fall also upon the treasury officials who reallocated enormous sums at his behest, upon the people who saw him daily and advised him, and lastly upon the people of Rome themselves, who cheered him at the Circus and theater. If Caligula was mad, why wasn’t he silently removed from public view and placed under the care of a physician—just as was done when rulers in later European history became mentally ill?

By no means do all modern authors assume Caligula was insane. In view of the clearly denunciatory tendency of the ancient sources, a number of scholars—notably Willrich, Gelzer, Balsdon, and Barrett—have attempted to clarify what actually occurred under his rule. Great progress has been made on some particular questions: By comparing contemporaneous sources and earlier traditions with later ones, it has been possible to weed out false information, like the allegation of incest. Assertions by ancient authors that contradict the intention of their own works—statements that have crept in by mistake, as it were, or references to events too well known to be omitted—have been shown to be reliable. And finally scholars can draw on the entire body of surviving documents to become familiar with the broader context of the times and develop a theory of the politics, society, religion, and mindsets of the period; this makes it possible to distinguish between plausible and implausible reports in the sources. To some extent modern scholarship has gone too far in transforming a ruler depicted as immoral and insane into a good one whose actions were rational. Above all, however, one question remains open: How can one explain the intense hatred for Caligula that is expressed in ancient accounts of him?

Almost all the sources can be traced back to members of the Roman aristocracy. They stem from senators and knights who were in direct contact with the emperor. Thus even their false statements about Caligula contain a degree of historical truth: The Roman aristocracy must have experienced such appalling things under his rule that posthumously he was tarred with the worst possible stigma: He was reviled as a monster and a madman and thus expelled outright from human society.

* Citations from ancient sources are based on the translations in the Loeb Classical Library; the full forms for the abbreviations used for authors’ names and works are listed on page vii.



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