In 44 BCE, Julius Caesar is assassinated by a conspiracy of about 60 senators led by Marcus Brutus, Cassius, and Decimus Brutus, triggering a chaotic power struggle in Rome. Octavian, an 18-year-old with no army and few allies, is unexpectedly named Caesar’s adopted son and primary heir in Caesar’s will. Over the next 15 years, Octavian systematically destroys all his rivals and becomes Augustus Caesar, the first Roman emperor. The central question of the episode is how Octavian, who was neither brilliant, charismatic, nor a great military commander, managed to triumph over far more experienced and powerful competitors.
The Assassination and Its Aftermath
The three main conspirators each had different motivations:
Decimus Brutus was Caesar’s most competent general and was driven by jealousy and ambition, wanting to prove himself superior to Caesar.
Cassius had fought for Pompey the Great, and after Caesar showed him mercy and made him a general, Cassius may have interpreted that mercy as contempt, motivating a desire for vengeance.
Marcus Brutus is the most complex case: he fought for Pompey but was also widely believed to be Caesar’s biological son (by Caesar’s mistress Servilia). Caesar had specifically ordered his soldiers to capture Brutus alive in battle, adopted him, and fast-tracked his career. Yet Brutus became the leader of the conspiracy. Shakespeare’s play argues Brutus was driven by vanity and a sense of duty—he believed he was named after Lucius Brutus, the founder of the Republic, and had a responsibility to save Rome from a would-be tyrant.
What united all the conspirators was a shared feeling that Rome was changing too fast under Caesar’s reforms, which, while beneficial in the long term, threatened the short-term interests of the nobility and disturbed the conservative Roman populace.
Caesar could not imagine he would be killed because of deep Roman taboos:
The pomerium (boundary of Rome) was sacred space where no weapons or violence were permitted.
The Senate was considered the most sacred and divine space in Rome, where violence was unthinkable.
Caesar’s body had been declared sacred and inviolable by the Senate.
Every senator had been personally appointed by Caesar and owed their position to his generosity.
Caesar did not want to become king because kingship was the ultimate taboo in Rome. He saw himself as a more merciful version of Sulla—a dictator who would make necessary reforms and then retire, preserving the Republic. The previous dictator Sulla had also refused to become king for the same reason.
Only five of the sixty conspirators actually physically attacked Caesar; the rest stood paralyzed by the taboo of committing violence in the Senate. The first attacker was shaking and only managed a pinprick wound in Caesar’s back—the origin of the term “backstabbing.” Even as he was being stabbed, Caesar could not believe anyone would break these sacred taboos.
How Caesar’s Death Transformed His Myth
The assassination backfired catastrophically for the conspirators because it proved Caesar had not wanted to become king:
While Caesar was alive, the Roman people were skeptical and feared his ambition. After his death, they felt tremendous guilt for doubting him, since it was that doubt which had allowed the conspirators to act.
Caesar’s will showered the Roman people with extraordinary generosity: every citizen received three months of a soldier’s wage, and much of his private property was turned into public parks. This demonstrated his love for the people.
The conspirators themselves realized they could only have killed Caesar because he refused to surround himself with bodyguards or act like a tyrant. Marcus Brutus, when urged by Cassius to aid Decimus Brutus against Mark Antony, refused to act—because moving his army against Rome would make him the ambitious one, the would-be king, proving he had been wrong about Caesar all along.
The death of Caesar turned his myth into reality: he was now remembered as a man of destiny who only wanted to save the Republic, not destroy it. This new reality, and the love and guilt of the Roman people, became the foundation of Octavian’s power.
Caesar’s Will and the Rise of Octavian
Caesar’s will contained three shocking provisions:
Every Roman citizen would receive three months of a soldier’s wage, and much of Caesar’s property would become public parks.
Caesar named not Mark Antony but a relative, Gaius Octavius (Octavian), as his adopted son and primary heir. Upon adoption, Octavian’s name became Gaius Julius Caesar Octavianus (shortened by historians to “Octavian”).
Mark Antony and Decimus Brutus (one of the assassins!) were named secondary heirs, demonstrating Caesar’s love even for those who conspired against him.
Octavian was only 18 years old, had no army, and had few allies in Rome. When he returned to claim his legacy, Mark Antony refused to meet with him and refused to hand over Caesar’s property and wealth.
To honor Caesar’s will, Octavian borrowed an enormous sum of money to ensure every Roman citizen received the three months of wages Caesar had promised. This act of honoring his adoptive father’s generosity won him enormous popular support.
The Power Struggle: A Game of Thrones
The political landscape after Caesar’s assassination was a volatile multi-sided conflict:
Octavian wanted to be recognized as Caesar’s heir, but so did Mark Antony and Lepidus.
Mark Antony, as consul (head of state), had initially reached a peace agreement with the conspirators but then worked to turn public opinion against them, forcing them to flee Rome.
The conspirators (Decimus Brutus in Gaul, Marcus Brutus and Cassius in the Roman East) commanded huge armies—about 100,000 soldiers, the largest army ever assembled in Roman history.
Lepidus was a competent administrator with his own army who wanted to avenge Caesar but was stopped by Antony.
Cicero, the last remaining Optimate (conservative who believed in Senate supremacy), controlled the Senate and tried to play all sides against each other to maintain the Senate’s authority and his own power.
Octavian’s Path to Sole Power
Octavian’s rise unfolded in stages over roughly 15 years:
Cicero, trying to maintain balance, authorized Octavian to raise an army to challenge Mark Antony, who was at war with Decimus Brutus in Gaul.
After Antony defeated Decimus Brutus, he absorbed Lepidus’s army. Then Antony, Octavian, and Lepidus sat down together and formed the Second Triumvirate, a formal three-man dictatorship.
The Triumvirate was brutal: they killed about a third of the Senate (including Cicero, who had previously been Octavian’s patron) and replaced them with allies.
Octavian and Antony then marched against Marcus Brutus and Cassius, defeating them at the Battle of Philippi in Macedonia in 42 BCE—the largest battle in history at that time. Both Brutus and Cassius were killed.
The three triumvirs divided the Roman world: Octavian got Rome, Lepidus got North Africa, and Mark Antony got Egypt and the Near East (the wealthiest share).
Lepidus later came into conflict with Octavian; Octavian gave a speech to Lepidus’s soldiers, who all defected to him, neutralizing Lepidus.
The final conflict was between Octavian and Mark Antony. At the Battle of Actium in 31 BCE in Greece, Antony’s forces (aligned with Cleopatra) fought Octavian’s. Antony and Cleopatra fled the battle, returned to Alexandria, and both committed suicide before Octavian could capture them.
In 27 BCE, Octavian returned to Rome in triumph and the Senate declared him Augustus Caesar, the first emperor of Rome.
Why Octavian Won: Evaluating the Explanations
Luck: Insufficient—one does not become emperor by luck alone.
Brilliance: Octavian was not brilliant in the traditional sense. He lacked Caesar’s charisma, his oratory was inferior to Mark Antony’s, and he was widely considered a terrible military strategist who lost many battles. He was, however, a brilliant political manipulator.
Ruthlessness: True but not distinctive—everyone in Roman politics was ruthless, and Mark Antony was especially so (he killed his own wife).
Legion loyalty to Caesar’s name: The legions did transfer their loyalty to Caesar’s adopted son, but they were also loyal to Mark Antony, who arguably had a stronger claim.
Marcus Agrippa: Octavian’s partner was a brilliant general responsible for most of Octavian’s major military victories, including Actius. But other factions also had brilliant generals (Cassius, Decimus Brutus), and this doesn’t explain why Agrippa stayed loyal to Octavian in such a treacherous political environment.
The episode’s central argument: Caesar’s assassination transformed his myth into reality. The Roman people’s love for Caesar—intensified by guilt—propelled Octavian to power. Octavian believed himself to be Caesar’s rightful heir, had a responsibility to finish his father’s mission of restoring the Republic, and was willing to act when others (like Marcus Brutus) were paralyzed. This belief system also explains why Marcus Agrippa trusted and stayed loyal to him—they were both fighting for Caesar’s legacy. The Roman people, taught to fear kings, gradually allowed Octavian to amass more power than any king because they believed, as they had come to believe of Caesar, that he was driven by a mission to save the Republic.
Mark Antony’s Self-Destruction
Mark Antony loved Caesar so much that he wanted to continue his legacy, but he felt betrayed when Caesar named Octavian, not him, as heir. His desperate need to prove he was Caesar’s rightful successor led to a series of self-destructive decisions:
He invaded Parthia (Rome’s last great enemy) to finish what Caesar had planned, but Romans were poorly suited to fighting Parthian cavalry. Antony was badly defeated, fell into depression, and became a drunk.
He became the lover of Cleopatra, Caesar’s former mistress (rumored to be the woman Caesar would have retired with). To be with her, he divorced his wife, who was Octavian’s sister, creating a personal rift.
In his will, he left all his territories in the East to his children with Cleopatra—foreign citizens—and he had no authority to do so (only the Senate could). Octavian used this will as a pretext to attack Antony, with strong popular support.
Antony’s attempts to escape Caesar’s shadow and prove his legitimacy guaranteed his own destruction.
Lepidus and the Others
Lepidus was an effective administrator but lacked the charisma and confidence to challenge Octavian. His soldiers defected to Octavian once they sensed his insecurity, drawn by Octavian’s status as Caesar’s son.
Augustus’s Rule and the Succession Problem
Augustus Caesar ruled for 40 years and was considered the first and greatest Roman emperor. Like Caesar, he did not call himself emperor but rather “First Citizen” (princeps), claiming his role was to ensure the eternal prosperity and stability of the Republic.
He concentrated enormous power in his own hands:
He made Egypt his personal property (a private estate), using its vast wealth to pay the army directly, making the legions loyal to the emperor rather than the Senate.
He gave land in Gaul (which Caesar had depopulated through genocide) to his veterans, further binding the army to him personally.
The Roman people allowed this concentration of power because they believed Augustus, like Caesar, was driven by a mission to restore the Republic.
Augustus’s succession solution was to adopt the most competent relative as emperor, creating a system where the best man would always be chosen:
He identified Germanicus as the ideal successor—brilliant, a great speaker, loved by his soldiers, much like Julius Caesar. But Germanicus was too young.
Augustus appointed his stepson Tiberius as a transitional emperor—competent but not charismatic, expected to rule for 5–10 years until Germanicus came of age.
The system broke down almost immediately: Tiberius, unwilling to let someone else choose his successor, killed Germanicus and his entire family, then adopted the notoriously bad emperor Caligula (Germanicus’s youngest son). Tiberius’s reign marked the effective death of the Roman Empire as a functional state—though it continued for another 300 years, it was racked by internal revolts and tensions, sustained only by its size and inertia.
