Ancient Rome · 31 BCE–14 CE

How Did Augustus Become Rome's First Emperor?

By the Aurelius editorial team · 3 min read · Updated 15 October 2026

Last time: Caesar's assassins restored nothing. His will named an 18-year-old great-nephew as his son and heir.

In January 27 BCE, the most powerful man in the Roman world told the Senate he was handing the Republic back. The senators begged him to stay in charge, gave him the provinces where most of the legions were stationed, and voted him a new name: Augustus.

A boy with a name

Gaius Octavius took his adoptive father's name and called himself Caesar; historians call him Octavian to avoid confusion. Mark Antony sneered that he was “a boy who owes everything to a name”. But the name brought Caesar's money and the loyalty of Caesar's veterans, and Octavian used both without scruple.

In 43 BCE he joined Antony and Lepidus as a board of three with power to remake the state. They revived Sulla's proscriptions, and among the victims was Cicero, the Republic's most famous orator. At Philippi in 42 BCE they destroyed Caesar's assassins, then divided the empire between them.

Actium

The partnership with Antony, who ruled the East with Cleopatra, turned into rivalry. Octavian's propaganda presented the coming war as Rome against a foreign queen rather than another civil war. At Actium off western Greece, on 2 September 31 BCE, his fleet under his friend Marcus Agrippa defeated theirs. A year later Antony and Cleopatra killed themselves in Alexandria, and Egypt's treasure paid Octavian's soldiers.

Giving power back, and keeping it

By 30 BCE Octavian had no rivals left. Caesar had been killed for looking like a king, so Octavian did the opposite. In 27 BCE he “restored the Republic”, then accepted command of the provinces with the legions. Some proposed he be called Romulus, as Rome's second founder; he chose Augustus, “the revered one”, a name with religious weight and no royal baggage.

He called himself princeps, “first citizen”. In 23 BCE he gave up the yearly consulship and took instead the powers of a tribune for life, the office the Gracchi had used to defy the Senate, and he counted the years of his rule by them. The Senate, the magistrates and the assemblies all still met. None of them could act against him.

Peace and marble

Augustus advertised peace. The doors of the Temple of Janus, closed only when Rome was at peace, were shut three times during his rule; he boasted that this had happened only twice before in Rome's history. The Senate voted the Altar of Augustan Peace, the Ara Pacis, in 13 BCE. He claimed he had found Rome a city of brick and left it a city of marble.

The peace had limits. Rome kept fighting on its frontiers, and in 9 CE three legions under Quintilius Varus were wiped out in Germany's Teutoburg Forest. Suetonius says the old emperor beat his head against a door, crying, “Quintilius Varus, give me back my legions!”

No word for what he was

The system had no name and no rule of succession. Augustus's chosen heirs died one after another: his nephew Marcellus, his friend and son-in-law Agrippa, and his grandsons Gaius and Lucius. At last he adopted his stepson Tiberius. When Augustus died at Nola on 19 August 14 CE, he had ruled for a little over 40 years since 27 BCE.

Suetonius says that on his last day he asked his friends whether he had played his part in the comedy of life well. Tacitus, writing a century later, was blunter: by the end, he asked, how many people were left who had seen the Republic?

In their own words

“In my sixth and seventh consulships, after I had extinguished civil wars, and at a time when with universal consent I was in complete control of affairs, I transferred the republic from my power to the dominion of the senate and people of Rome… After this time I excelled all in influence, although I possessed no more official power than others who were my colleagues in the several magistracies.”

Augustus, Res Gestae Divi Augusti (The Deeds of the Divine Augustus) 34, completed by 14 CE

Augustus's own account, set up on bronze pillars outside his mausoleum; the best surviving copy is on the temple walls in Ankara. “Influence” translates auctoritas and “official power” potestas. Translation after P. A. Brunt and J. M. Moore (1967).

Why it happened

• Caesar's name, money and veterans gave Octavian a power base at 18.
• Victory over Antony and Cleopatra left him without rivals.
• Caesar's murder taught him to hide one-man rule behind republican forms.
• After decades of civil war, many Romans valued peace more than political liberty.

What happened next

• Rome became a monarchy ruled by emperors, though no law ever said so.
• Egypt became a Roman province under the emperor's personal control. Read the story →
• Because succession was never defined, many later reigns ended in murder, civil war or both. Read the story →

Why it still matters

Augustus showed that one person can hold power while every institution keeps its forms. The method is still in use. In 2008 Vladimir Putin, barred from a third consecutive term as Russia's president, became prime minister while his protégé Dmitry Medvedev held the presidency; he returned to it in 2012, and a 2020 constitutional amendment reset his count of terms. The forms were obeyed; the power never moved.

Connected stories

• The Ides of March: Caesar's murder gave Octavian his name and fortune, and the lesson never to look like a king.
• Cleopatra: The Last Queen of Egypt: Cleopatra's alliance with Antony let Octavian present the last civil war as a foreign war.
• The Gracchi and the Crisis of the Republic: The tribune's powers that the Gracchi used against the Senate became the legal core of an emperor's authority.
• The Founding of Rome: Legend and Evidence: Octavian was offered the name Romulus, as Rome's second founder, and chose Augustus instead.

Sources

• Augustus, Res Gestae Divi Augusti
• Suetonius, Life of the Deified Augustus
• Tacitus, Annals 1.1–1.10
• Adrian Goldsworthy, Augustus: First Emperor of Rome (2014)

Images are credited under each picture. Paintings and photographs come from public collections via Wikimedia Commons; scenes with no surviving image are marked as illustrations.