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. 9.2.5.2). 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.
ONE
Childhood and Youth
Gaius Caesar Germanicus was born on 31 August in the year A.D. 12 to Germanicus and the elder Agrippina. At the time no one could have foreseen that at the age of only twenty-four this young man, known by then under his nickname, “Caligula,” would become Roman emperor. On 18 March 37, he would become ruler of an empire that spanned virtually the entire known world of antiquity, from Syria to the English Channel, from North Africa to the Danube region, and from Spain to Asia Minor. No one could have anticipated how many intrigues and murders, trials and executions would take place in Rome, the center of that Empire, in the two and a half decades leading up to his succession. Nor could anyone have possibly imagined in the year 12 how Gaius would come to exercise his rule in the end.
At the time of his birth, his great-grandfather Augustus was still in power. Although aristocrats criticized Augustus in private, they were all agreed on the most important achievement of his long sole rule (31 B.C.—A.D. 14): After almost a hundred years of violent political conflict and civil wars, which had affected the entire Mediterranean region and could be described in retrospect as a process of gathering monopolization of political power, Augustus had brought peace. Admittedly in doing so he had also ended the old collective rule of the aristocracy that had characterized the Roman Republic and functioned with great success for centuries, replacing it with a form of sole rule — something that had clearly become unavoidable. His exceptional position, which he had usurped during the civil war against Marcus Antonius, was based on military might, but he had not given it the form of monarchy, showing a restraint for which many of his senatorial coequals gave him credit. Instead he had chosen the term “principate,” which allowed him to appear as merely one of the first among citizens. At the same time he had reanimated the old political institutions and practices of the Republic: The Senate met and debated; the magistrates in Rome and the provincial governors performed their tasks; the people assembled, voted, and decided — and acted on important questions only as Augustus wished. The emperor’s unrestricted control over the military was symbolized by his bodyguard, the elite Praetorians, whose presence and its import could not be overlooked. Nevertheless he had caused his unique position to be confirmed in Rome and the provinces in the traditional legal forms, showing that although he had drained the old Republican institutions of real power he still needed them to justify his authority. Thus a curious situation had arisen, one that demanded great communicative skill from all participants: The senators had to act as if they still possessed a degree of power that they no longer had, while the emperor had to exercise his power in such a way as to dissemble his possession of it.
Figure 2. Bust of Caligula. Heraklion, Archaeological Museum, 64.
How did this contradictory, historically unique combination of republic and monarchy come about? One social and one political reason can be named. Like all highly developed pre-modern cultures, ancient Rome had a stratified society, with a deep division between the nobility and the non-noble population. The exercise of authority, whether in the military or in the civic sphere, had always been limited to members of the upper class. Even though the common people were included in the political process during the Republic, it was precisely their behavior that reserved authority for the noble families. For although elections were held regularly and were technically open to non-noble candidates, again and again those elected to political office (and thus to positions of military leadership) came almost exclusively from the same noble families. They were evidently the only men whom the common people were prepared to obey. Every emperor faced this situation. He needed the leading members of the nobility to command the Roman legions throughout the Empire and to perform civic functions in Rome itself. This group was identical, however, to the approximately six hundred men who composed the membership of the Senate — the most important Republican political institution — and the core of the Roman aristocracy, with whom an emperor thus had to have some kind of workable entente.