How Julius Caesar Was Betrayed

The Man Who Made Himself Untouchable

By the winter of 45 BCE, Gaius Julius Caesar had achieved something no Roman had managed before him. He had won a civil war against the most powerful general of the previous generation, eliminated every serious military rival, and returned to Rome not as a victorious general who would eventually lay down his command, but as permanent dictator. The office of dictator existed in Roman constitutional tradition, but always as a temporary emergency measure. Caesar held it for life.

He accumulated titles and powers that strained every precedent. He was appointed dictator perpetuo, dictator in perpetuity. He held the consulship year after year. His portrait appeared on Roman coins while he was still alive, something previously reserved for gods and foreign kings. He wore the red boots of the ancient kings of Alba Longa. When the Senate met, he received them seated, like a king receiving petitioners.

Whether Caesar actually wanted to become king of Rome in the formal sense is a question historians have debated for two millennia. What is not disputed is that his behavior gave everyone around him reason to wonder. And for a class of men whose entire identity was built around the Republic and their own dignitas within it, that uncertainty was intolerable.

The Conspirators: Who They Were and Why They Acted

Approximately 60 senators participated in the conspiracy to assassinate Caesar. Their motives were not uniform, and the popular image of selfless republican idealists sacrificing personal interest for the good of Rome does not survive close examination.

Marcus Junius Brutus is the figure whose participation most troubled ancient sources, and still troubles modern ones. He was Caesar's protege, perhaps his illegitimate son (ancient gossip was confident about this, though modern historians are more skeptical). Caesar had pardoned him after Pharsalus, where Brutus had fought on the side of Pompey against Caesar. He had been given prestigious positions in Caesar's administration. His defection to the conspiracy was a genuine betrayal of a personal relationship, whatever its political justification.

Brutus's brother-in-law Gaius Cassius Longinus was the driving organizational force behind the plot. Unlike Brutus, whose motives mixed genuine republican ideology with personal grievance, Cassius had specific resentments: Caesar had passed over him for the post of senior praetor, giving the position to Brutus instead. Ancient sources describe Cassius as a man with a lean and hungry look, quoting Shakespeare, who was drawing on Plutarch. The portrait is of a man who combined ideological conviction with wounded pride.

Decimus Brutus Albinus, a different man from Marcus Brutus despite the shared name, was the conspirator whose participation Caesar would have found most shocking. He was one of Caesar's most trusted military commanders, a man who had dined with Caesar the night before the assassination. His role was to ensure Caesar arrived at the Senate meeting despite unfavorable omens and his wife Calpurnia's pleas that he stay home. Caesar trusted him completely.

The Planning

The conspiracy was organized over several weeks in early 44 BCE. The core group, primarily Brutus, Cassius, and Decimus Brutus, recruited additional senators carefully, choosing men who had reason to resent Caesar or who had sufficient republican credentials to give the act political legitimacy.

They debated whether to kill Mark Antony as well. Antony was Caesar's most powerful lieutenant and the man most likely to organize a counterattack on behalf of Caesar's legacy. Brutus argued against killing Antony, reportedly on the grounds that the conspiracy should appear to be tyrannicide, not a broader political purge. This decision would prove catastrophic for the conspirators.

They chose March 15, the Ides of March in the Roman calendar, as the date. A Senate meeting had been scheduled for that day in the Theater of Pompey, where the Senate was meeting temporarily while work on the Curia was completed. The location added a dark irony: Caesar would die in a building built by the general he had defeated.

The conspirators did not use professional assassins. Each senator who participated agreed to strike a blow himself. This was partly for security (professional killers could be bought off or might talk) and partly to distribute the moral and legal responsibility. If sixty senators had each struck Caesar, no single man could be held primarily accountable.

The Ides of March

The ancient sources, primarily Plutarch, Suetonius, and Appian, provide dramatic accounts of the day's events, though they were writing generations after the fact and drew on sources of variable reliability.

Caesar had received multiple warnings. A soothsayer named Spurinna had reportedly warned him to beware the Ides of March. His wife Calpurnia had nightmares the night before and begged him not to attend the Senate meeting. Caesar initially agreed to postpone. Then Decimus Brutus arrived and persuaded him that the Senate would mock him for staying home due to his wife's dreams. Caesar relented.

At the meeting, one of the conspirators, Tillius Cimber, presented a petition for his exiled brother's return as Caesar took his seat. As Caesar began to refuse, Cimber grabbed his toga and pulled it from his shoulder. This was the signal. The first blow was struck by Servilius Casca, who stabbed Caesar in the neck. Caesar grabbed the blade with his hands, cutting himself, and turned to face his attacker.

Then the rest of the senators fell on him. The ancient sources report twenty-three stab wounds in total. A physician later determined that only one, the second wound to the chest, was actually fatal. Most of the blows landed in the chaos and struck already dead or dying flesh, or struck other conspirators by accident. Caesar fell at the base of a statue of Pompey.

His last words, if any were spoken, are not known. The famous "Et tu, Brute?" is Shakespeare's invention, based loosely on Suetonius's report that Caesar said, in Greek, "kai su, teknon?" ("you too, child?") to Brutus, a phrase whose meaning is debated and whose authenticity is uncertain.

The Immediate Aftermath

The conspirators had planned the assassination. They had not planned what came next. They expected the Senate to applaud, to confirm the act as tyrannicide, and to restore the Republic. Instead, the Senate fled in panic. The Roman people, whom the conspirators expected to welcome their liberation, stayed inside. The Forum was empty.

Mark Antony, warned of the assassination before it happened, had not gone to the Senate meeting. He secured Caesar's papers and treasury from Calpurnia, who cooperated because Antony was the only man with both the authority and the motivation to manage the crisis. Antony delivered Caesar's funeral oration in the Roman Forum, read Caesar's will publicly (it left substantial gifts to the Roman people), and displayed Caesar's blood-soaked toga to the crowd. The crowd became a mob. They tried to burn the Senate house. Several conspirators' houses were attacked.

Brutus and Cassius left Rome within weeks. They never returned.

What the Conspiracy Actually Achieved

The conspirators failed on their own terms. Their stated goal was to restore the Roman Republic. What they produced was seventeen more years of civil war that ended with a system more monarchical than anything Caesar had established, an emperor with permanent sole authority over the Roman world, a position that would persist for another five centuries in the west and over a millennium in the east.

Caesar's heir, his 19-year-old grand-nephew Gaius Octavius, whom Caesar had adopted in his will, proved far more politically sophisticated than his assassins. He allied with Antony against them, defeated them militarily, then eventually outmaneuvered Antony as well. He became Augustus, the first Roman emperor, in 27 BCE. He was careful never to claim the title of king. He accumulated the same powers Caesar had held, but distributed them across enough traditional offices that the constitutional fiction of the Republic could be maintained.

The conspirators had misread their own society. Rome in 44 BCE was no longer the city-state Republic of the early centuries, small enough that its citizens could actually participate in its governance. It was the capital of a Mediterranean empire with hundreds of millions of subjects. That structure required autocratic management. Caesar had understood this. His assassins had not. They killed the man but could not kill the historical process that had produced him.