1. Julius Caesar was his great-uncle and adopted father.

Born on September 23, 63 B.C., Augustus grew up in a town about 25 miles southeast of Rome. His father was a senator (who died unexpectedly when he was four), and his mother was Caesar’s niece. As a child, Augustus presumably saw little to none of his famous great-uncle, who was out invading Gaul.

Eventually, however, he gained Caesar’s trust and began spending more and more time with him, including during a military campaign in Spain. Thanks to his great-uncle, Augustus was able to join the patrician aristocracy, just one of many honors bestowed on him. Then, after a group of senators assassinated Caesar in 44 B.C., Augustus learned of the conqueror’s recently redrawn will, in which he was posthumously adopted and bequeathed a generous inheritance.

2. Augustus was not his birth name.

Originally called Gaius Octavius, he changed his name to Gaius Julius Caesar Octavianus, aka Octavian, upon being adopted by his great-uncle. Seventeen years later, the Senate awarded him with the name Augustus, meaning “Revered One.” He also collected numerous titles over the course of his life, such as pontifex maximus (chief priest), princeps (first citizen), imperator (commander in chief) and divi filius (son of a god), the last of which he took on following Caesar’s deification by the Senate.

Notably, Augustus never referred to himself in monarchical or dictatorial tones, and he lived in relatively modest quarters. Yet because he amassed supreme power, historians refer to him as Rome’s first emperor.

3. His sister married his fiercest rival.

Following Caesar’s death, the teenage Augustus raised an army and went to war with Mark Antony, Caesar’s former deputy who likewise considered himself the conqueror’s political heir. Upon winning his first battle against Antony, Augustus marched on Rome and was elected consul, the highest office of the Roman Republic. He then entered into the so-called Second Triumvirate, in which he, Antony and Marcus Aemilius Lepidus agreed to divide Rome’s territories between them.

As one of their first orders of business, they teamed up to defeat Caesar’s assassins. Meanwhile, in order to solidify the alliance, Antony married Augustus’ sister, and Augustus married Antony’s stepdaughter. Neither marriage lasted, however, nor did the triumvirate. The final break came in 32 B.C., when Augustus used an illicitly obtained copy of Antony’s will to rail against him and his high-profile mistress, the Egyptian queen Cleopatra. In the civil war that followed, Augustus blockaded Antony’s force off the western coast of Greece.

Though Antony and Cleopatra escaped to Egypt, the majority of their soldiers surrendered, and they both ended up committing suicide as Augustus closed in on them. To add insult to injury, Augustus ordered that Antony’s heir be killed, along with a son that Cleopatra had with Caesar.

4. He nearly doubled the size of the empire.

Having vanquished his rivals, Augustus set about consolidating his power, improving Rome’s infrastructure and beautifying the city. He also looked to expand the empire’s borders, bringing Egypt, northern Spain, the Alps and much of the Balkans under Roman control. Progress was made in Germany as well, until three legions were wiped out in an ambush in A.D. 9, forcing the Romans to withdraw west of the Rhine River.

Upon hearing news of the defeat, Augustus repeatedly banged his head against the wall and yelled out for the general in charge to “give me back my legions,” according to a Roman historian. As part of these expansion efforts, Augustus spent years in Spain, Gaul, Greece and Asia. Yet he was not much of a fighter himself, often getting sick on the eve of combat and depending heavily for strategy on his boyhood friend Marcus Vipsanius Agrippa.

5. The month of August was named after him.

With Rome in an era of relative peace and prosperity, the Senate voted in 8 B.C. to rename the month of Sextilis after Augustus. During that month, the Senate purportedly explained in its decree, Augustus had first become consul and had won his final victory over Antony and Cleopatra. On the calendar, it followed July (formerly Quintilis), which had recently been renamed in honor of Julius Caesar.

6. He sent his own daughter into exile.

A proponent of traditional values, Augustus built and refurbished myriad temples during his reign, encouraged marriage and childbirth, and criminalized adultery despite allegedly being wildly unfaithful himself. When he discovered in 2 B.C. that his only child, Julia, had been sleeping out of wedlock with numerous influential men, including Mark Antony’s son, he banished her to the rocky island of Ventotene.

Although he later allowed her to transfer to a less-isolated locale, he never saw her again. Augustus likewise banished his granddaughter for alleged adultery, though in both cases historians believe additional factors may have been in play.

7. His potential heirs kept mysteriously dying.

With no son of his own, Augustus spent considerable time and energy trying to cultivate a successor. He focused his early attentions on his nephew Marcellus, whom he married off to Julia in 25 B.C. But Marcellus fell ill and died a couple of years later around age 21. Next, Augustus turned to Agrippa, his friend and general, who, though 25 years older than Julia, produced three sons and two daughters with her.

Augustus adopted and helped raise the two older boys, Gaius and Lucius, only to see the first die at age 23 after being wounded in Armenia and the second die at age 19 after contracting an unknown disease in Gaul. Julia and Agrippa’s third son, on the other hand, was purportedly full of rage and sent into exile.

Following Agrippa’s death, Augustus forced his stepson Tiberius to divorce his beloved wife and marry Julia instead, but they only had one child together who died in infancy. His options having considerably dwindled, Augustus finally turned with reluctance to Tiberius, who would go on to rule Rome from A.D. 14 to A.D. 37. Rumors spread that Tiberius’ mother (Augustus’ third and final wife) had killed off the other potential heirs so that her son would get the job, but no concrete evidence has ever emerged to that effect.

8. The next five emperors were all his relatives.

Augustus’ reputation as the bringer of stability to Rome proved so strong that the emperorship remained in his family until A.D. 68, when Nero committed suicide after being deposed in a coup. Though a short civil war broke out—four emperors served in A.D. 69 alone—it was a minor blip in the 200-year Pax Romana (Roman Peace) that Augustus had ushered in. The empire itself, meanwhile, would survive in one form or another until the 15th century.

HISTORY Vault: Colosseum

The Roman Empire is vividly brought to life through the lens of the Colosseum.