Who Was the First Emperor of Rome? Augustus, Explained

Augustus turned a republic worn out by civil war into an empire that lasted for centuries, yet he never called himself king or emperor. Below you will find who he was, how he took power step by step, why so many people think Julius Caesar came first, and the places in Rome where you can still follow in his footsteps.

Augustus was born Gaius Octavius on 23 September 63 BC in Rome, in the Palatine quarter, according to his biographer Suetonius. His father's family came from Velitrae (today's Velletri), a town in the hills south of Rome. His mother, Atia, was the niece of Julius Caesar, which made Caesar his great-uncle.

Caesar had no legitimate son. In his will he adopted Octavius and made him his chief heir. When Caesar was murdered in March 44 BC, the 18-year-old took the name Gaius Julius Caesar. Historians call him Octavian for the years before 27 BC, to avoid confusing him with his famous adoptive father.

He ruled for more than four decades and died at Nola, near Naples, on 19 August AD 14, aged 75. A month later, on 17 September, the Senate declared him a god.

Key facts about Augustus, the first Roman emperor, from his birth in 63 BC to his death in AD 14

Octavian did not seize power in a single day. It took him 17 years of politics and war.

First he joined forces with Caesar's general Mark Antony and the politician Lepidus. In November 43 BC the three men were formally appointed as the Second Triumvirate, with near-total power. Together they defeated Caesar's assassins Brutus and Cassius at Philippi in 42 BC.

The alliance did not last. Antony ruled the eastern provinces with Cleopatra, queen of Egypt, while Octavian held Italy and the West. On 2 September 31 BC, Octavian's fleet, commanded by his friend Marcus Agrippa, beat Antony and Cleopatra at the Battle of Actium off the coast of Greece. A year later both had taken their own lives, and Egypt became a Roman province.

Octavian was now the only man with an army that mattered. In January 27 BC he made a show of handing the state back to the Senate. Four days later, on 16 January 27 BC, the grateful senators gave him the name Augustus, meaning "the revered one". Some had wanted to call him Romulus, after Rome's founder.

From Republic to Empire in a short timeline

Timeline of how Octavian became Augustus, the first Roman emperor, from 44 BC to AD 14

Most historians date the beginning of the Roman Empire to 27 BC, the year Octavian became Augustus. Britannica, for example, dates the Roman Republic from 509 to 27 BC. Some historians prefer 31 BC, the year of Actium, because that victory left Octavian without a rival.

What makes the question tricky is that nothing officially changed. The Senate kept meeting, consuls were still elected and Augustus insisted the Republic had been restored. He presented himself as the princeps, the "first citizen", an informal label rather than an official title. The real power lay in the army, the provinces he controlled and the authority of a tribune, which he held for life from 23 BC. The Romans themselves counted an emperor's years of rule from that tribunician power.

So the empire did not begin with a coronation. It began when one man quietly held all the powers that the Republic had once divided.

No. Julius Caesar was never a Roman emperor. He was a general and politician who held the office of dictator, a recognised, normally temporary office of the Roman Republic. In early 44 BC he was named dictator for life, and only weeks later, on the Ides of March (15 March) 44 BC, he was stabbed to death by a group of senators who feared he wanted to become king.

A marble portrait bust of Julius Caesar

There are three reasons people still call him the first emperor:

The difference is that Caesar left behind no lasting system of government and no secure succession. Augustus built both.

Comparison of Julius Caesar and Augustus showing why Augustus counts as the first Roman emperor

Augustus's rule began the Pax Romana, the "Roman peace", a period of about two centuries of relative stability that historians usually date from 27 BC to the death of Marcus Aurelius in AD 180.

He also transformed the city itself. Suetonius reports that Augustus boasted he had found Rome built of brick and left it in marble. In his own account of his reign, the Res Gestae, he lists 82 temples he restored in a single year, 28 BC. He built the Forum of Augustus with its Temple of Mars Ultor, inaugurated in 2 BC, and the Ara Pacis, the Altar of Augustan Peace, dedicated on 30 January 9 BC. His friend Marcus Agrippa built the first Pantheon, whose inscription still carries Agrippa's name.

Even the calendar remembers him. In 8 BC the month Sextilis was renamed August in his honour. He picked it over his birth month, September, because his first consulship and his greatest victories had fallen in it.

Augustus spent years trying to find an heir. In the end he adopted his stepson Tiberius in AD 4, and Tiberius took over when Augustus died. Their family, known as the Julio-Claudian dynasty, ruled until the death of Nero in AD 68.

It was under Tiberius that Jesus was crucified in Judea, as we explain in which Roman emperor ruled when Jesus died. After Nero's death, AD 69 became the Year of the Four Emperors, and the winner, Vespasian, went on to build the Colosseum.

Bar chart of how long the first five Roman emperors ruled, from Augustus to Nero

Augustus's Rome is still all around you in the city centre. Here is what you can see in 2026:

The Roman Forum, the Palatine and the Colosseum lie side by side, so you can see the world Augustus created and the arena his successors built in one visit. For the most atmospheric version, join one of the best Colosseum night tours, when the monuments are floodlit and the crowds have gone. To see how the story ends, read how long Rome lasted after Augustus.