The Twelve Caesars

• 1. Introduction

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  The Twelve Caesars arrives in the historical record already trailing a secret: its author, Gaius Suetonius Tranquillus, had access to the imperial archives of Rome and then lost it. He wrote the book in 121 AD, serving as personal secretary to the emperor Hadrian. He dedicated it to his friend Gaius Septicius Clarus, the Praetorian prefect. What he produced was not a sober chronicle of military campaigns and legislation. It was something stranger and more durable: twelve portraits of Julius Caesar and the first eleven emperors of Rome, shot through with gossip, omens, physical descriptions, sexual scandals, and small human details that no other surviving source bothered to preserve.

  The subjects line up in order: Julius Caesar, Augustus, Tiberius, Caligula, Claudius, Nero, Galba, Otho, Vitellius, Vespasian, Titus, Domitian. Some ruled for decades. Others barely lasted months. Suetonius gives each man a biography, and historians have been quarreling with those biographies ever since. Was he too reliant on hearsay? Too quick to sacrifice accuracy for a good story? And yet, for certain emperors, including Caligula, Claudius, and Vespasian, Suetonius remains the primary surviving source. Other accounts, including the relevant sections of Tacitus' Annals, have simply been lost. The questions hanging over The Twelve Caesars are the same ones that haunt all ancient history: who gets remembered, who decides how, and what survives the centuries.

• 2. The Man Behind the Work

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  Suetonius never sat in the Senate. He shared the Senate's perspective in most of its conflicts with the emperors, producing biases he may not always have recognized in himself. His father had been an army officer who fought for Otho against Vitellius at the first Battle of Bedriacum, a fact that colored at least one biography in ways the text itself acknowledges. When he wrote about Vitellius, he was working inside an era when Vespasian's Flavian dynasty had effectively controlled how history remembered that chaotic year.

  His access to official archives gave him materials no one else had gathered. He drew on the letters of Augustus, which he collected before losing archive access, and quoted directly from the emperor's will. But by the time he reached Claudius, the archives were gone. He was forced to rely on secondhand accounts, hearsay, and rumor. He does not quote Claudius the way he quotes Augustus. The change is visible in the texture of the writing.

  Historians have criticized him on several grounds. He appears to include subjective opinions within passages that read as objective reporting. He omits significant events without explanation. He treats gossip and verified fact with sometimes indistinguishable confidence. Yet the collection survives, along with the works of Tacitus, as one of the enduring primary sources for classical scholarship, largely because of the small details he preserved that no one else thought worth recording.

• 3. Caesar Unvarnished

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  Suetonius begins his account of Julius Caesar not with a triumph or a law but with a teenage boy. Caesar was sixteen when his father died. Suetonius describes Caesar's relationship at that time with a wealthy woman named Cossutia, then his engagement to Cornelia during the civic strife that followed. From this domestic opening, the portrait gradually takes on harder edges.

  The pirate episode is one Suetonius clearly relished. A young Caesar was captured in the Mediterranean Sea, and when his captors named a ransom, he found it insulting. He insisted they raise the price to 50 talents. He spent his captivity treating the pirates as subordinates, forcing them to listen to his speeches and poetry, and promising, as a kind of joke, that he would one day crucify them. After about a month, the ransom was paid and Caesar was released. He then raised an army on his own authority, holding no public office, captured the same pirates, and crucified them. He also recovered the 50 talents.

  Suetonius quotes Caesar's famous remark about Pompey during a battle he nearly lost: "That man does not know how to win a war." He also records Caesar's visit to a statue of Alexander the Great while serving as quaestor in Hispania. Caesar fell to his knees weeping, and explained that by Alexander's age, Alexander had conquered the whole world. These details portray a man consumed by competitive ambition before he had any conventional basis for it.

  On his physical appearance, Suetonius notes that Caesar was semi-bald and combed his hair forward to conceal it. He wore a senator's tunic with an orange belt and preferred loose-fitting clothes, which earned him a warning from the dictator Lucius Cornelius Sulla: "Beware the boy with the loose clothes, for one day he will mean the ruin of the Republic."

  On the day of the assassination, Caesar was handed a document describing the entire plot. He never had a chance to read it. As for his last words, Suetonius is careful to distinguish between what others have claimed and what he himself believes. Others reported the reproach to Brutus, "You too, my child?" But Suetonius asserts that Caesar said nothing as he was being stabbed, apart from a single groan. His only words, Suetonius reports, came as the attack began: "Why, this is violence!"

• 4. Augustus and the Weight of Peace

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  Gaius Octavius became Augustus, "the venerable," by title of the Roman Senate after defeating his last surviving rival, Mark Antony, at the Battle of Actium in 31 BC. It was that victory that made him master of the Roman world. Antony committed suicide following his defeat, and the long era of civil wars that had begun under Julius Caesar was declared over. What followed was the Pax Romana.

  Suetonius devotes a substantial portion of the book to Augustus' personal life, in part because his reign was largely peaceful after Actium and in part because personal detail was precisely what Suetonius valued. Augustus, Suetonius reports, lived in an ordinary Roman house, ate ordinary meals, and slept in an ordinary bed. His relationship with his daughter Julia was strained. Julia was his only child, and Augustus had originally wanted her to provide a male heir. Her promiscuity led him to banish her to the island of Pandateria and to consider having her executed. Suetonius quotes Augustus cursing his enemies by wishing that they would have "a wife and children like mine."

  The most dramatic passage in the Augustus biography concerns the Battle of Teutoburg Forest in Germany, where three Roman legions, Legio XVII, Legio XVIII, and Legio XIX, were annihilated by a West-Germanic resistance led by Arminius. Suetonius records that this battle "almost wrecked the empire." Upon hearing the news, Augustus reportedly struck his head against a wall in despair and cried out repeatedly: "Quintili Vare, legiones redde!" which translates as "Quinctilius Varus, give me back my legions!" The defeat set the Rhine and Danube as Rome's permanent northern border. Rome never again pushed territory deeper into Germany, and Suetonius suggests Augustus never fully recovered from the loss.

  Omens and prophecy thread through the Augustus biography. In 63 BC, during the consulship of Cicero, several Roman senators dreamed that a king would be born to rescue the republic. That year was also the year Augustus was born.

• 5. Emperors at the Extreme

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  Caligula's nickname, meaning "little boots," came from his father's soldiers. As a boy he would dress in miniature battle gear and drill the troops, not knowing the commands; the soldiers pretended to understand him because they loved Germanicus, his father. Germanicus died in 19 AD before he could succeed Tiberius, and the goodwill the army felt for him transferred briefly to his son. Most of what survives about Caligula's reign comes from Suetonius. The relevant sections of Tacitus contain little, if anything.

  The catalogue of Caligula's behavior in Suetonius is relentless. He married his sister to a man named Lepidus while apparently still treating her as his wife. He threatened to make his horse consul. He had a walkway built between his palace and a temple so he could be closer to Jupiter, whom he considered his divine brother. He replaced the heads of statues of various gods with busts of his own head. He would summon people to his palace in the middle of the night, hide when they arrived, and make strange noises. He had people assassinated, then summoned them; when they failed to appear, he announced they must have committed suicide.

  Nero's portrait shares a similar structure, beginning with his path to the throne ahead of Claudius' son Britannicus, and descending into a catalog of personal extremes. Suetonius describes Nero as a gifted musician who held concerts that attendance was compelled for upper-class Romans, concerts that lasted for hours. Some men reportedly faked death to escape, since Nero forbade anyone from leaving before he finished. It is in Suetonius that the image of Nero watching Rome burn and singing an epic poem about the sack of Troy while playing the lyre first appears. Suetonius also reports that Nero was condemned to death by the Senate and committed suicide when he learned soldiers had been sent to kill him.

  The shortest biographies belong to Galba, Otho, and Vitellius, the three emperors of the Year of the Four Emperors who followed Nero. Suetonius notes that by the time he was writing about Galba, he had exhausted all his imperial archival sources. Otho, whose full name was Marcus Salvius Otho, reigned for only a few months. Suetonius describes his final night: realizing he would soon be murdered, Otho contemplated suicide, then decided to sleep one more night. He went to bed with a dagger under his pillow. The next morning, he woke and stabbed himself to death.

• 6. The Flavians

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  Vespasian, founder of the Flavian dynasty, came from humble origins, and Suetonius begins his biography with exactly that fact. Suetonius presents his early imperial actions, the restoration of discipline, the repair of infrastructure damaged in the civil wars, favorably, drawing explicit parallels with Augustus and describing him as modest, lenient, and extraordinarily just.

  The biography of Vespasian contains one of the most durable sayings in the collection. His son Titus criticized him for levying a fee for the use of public toilets in the streets of Rome. Vespasian produced some coins and asked Titus to smell them. Titus said they did not smell bad. Vespasian replied: "And yet they come from urine." This exchange became the origin of the expression Pecunia non olet, money has no odor.

  Vespasian's last recorded words arrived during a sudden attack of diarrhea on what would be his deathbed. He said, "An emperor ought to die standing," and died while struggling to do so.

  Titus, his elder son and the second Flavian emperor, was described by Suetonius as "the delight and darling of the human race." He had grown up in the imperial court alongside Britannicus, the son of Claudius, and the two were close enough that when Britannicus was poisoned at dinner, Titus, who was present, tasted the cup and was nearly killed. Titus made his military name in Germany and Britain but truly came into his own commanding the siege of Jerusalem under his father. That siege lasted nearly six months and ended with the destruction of Herod's Temple and the expulsion of Jews from the city, beginning the period known as the Jewish diaspora from around 70 AD to 1948. During his reign as emperor, he completed the Flavian Amphitheater. He died of a fever after reigning for, in Suetonius' exact phrase, "two years, two months and twenty days." His final recorded words were that life was being undeservedly taken from him, since only a single sin lay on his conscience.

  Domitian, the younger brother of Titus and the last of the Flavians, was murdered in 96 AD. The group responsible, according to Suetonius, included his wife, Domitia Longina, and possibly his successor, Nerva. Domitian's murder marked the beginning of the period known as the Five Good Emperors.

• 7. Survival and Influence

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  The oldest surviving copy of The Twelve Caesars was made in Tours in the late 8th or early 9th century AD. It is now held in the Bibliothèque nationale de France. That copy, along with every other surviving copy, is missing the prologue and the opening of the life of Julius Caesar. There are nineteen surviving copies from the 13th century or earlier, and they can be split into two branches of transmission of roughly equal size, based on which errors appear in which manuscripts.

  The book's survival was confirmed as early as the 6th century by John Lydus, whose work De magistratibus populi Romani quoted the dedication to Septicius Clarus from the now-lost prologue. Since the dedication identifies Septicius as Praetorian prefect, and he held that office from 119 to 121 AD, the quote allowed scholars to date the book precisely.

  The influence on later biography was immediate. Marius Maximus modeled his biographies of second- and early third-century emperors on The Twelve Caesars, producing a collection apparently titled Caesares that does not itself survive but fed into the Historia Augusta. In the 9th century, Einhard modeled his Life of Charlemagne on Suetonius, borrowing phrases from Suetonius' physical description of Augustus to describe Charlemagne.

  Robert Graves, best known for his historical novels I, Claudius and Claudius the God, produced a widely read English translation first published by Penguin Classics in 1957. In 2025, a translation by Tom Holland replaced it as the Penguin Classics edition. Suetonius also influenced coin collecting: for centuries, assembling a coin of each of the twelve Caesars has been a recognized challenge among collectors of Roman coins. Titian created a series of paintings of the Twelve Caesars, and the Aldobrandini Tazze, a set of twelve silver standing cups from the 16th century, followed the same theme.