Octavia Minor (circa 69 BCE to 11 BCE) was a Roman noblewoman who rose to prominence during the early years of the Roman Empire. The sister of Emperor Augustus (reign 27 BCE to 14 CE) and wife of Mark Antony (83 BCE to 30 BCE), she was known and respected throughout the Roman world for exemplifying traditional Roman virtues, and she became one of the first matriarchs of the Julio-Claudian Dynasty.

Octavia was born in the town of Nola in southern Italy, probably around 69 BCE – some scholars suggest that she was born a little later, with Katrina Moore offering 66 BCE as a potential birth year. She was a member of the gens Octavia, a noble plebeian family of modest origin. According to the historian Suetonius, the family was granted Roman citizenship by Lucius Tarquinius Priscus, the fifth king of Rome. During the era of the Roman Republic, they did not achieve anything of note until 230 BCE when a member of the family attained the office of questor. Since then, several Octavii reached high political offices. Still, at the time of Octavia's birth, they remained a relatively obscure family.

Her father, Gaius Octavius, was an up-and-coming politician whose career promised to put the family on the map. By the time of her birth, he had already served as military tribune and questor, beginning his climb up the political ladder; in time, he would also reach the office of praetor and serve as proconsul of Macedonia, a respectable career for a novus homo (literally, 'new man', the Roman term for the first man of a family to reach the Roman Senate). Initially, Octavius was married to a woman named Ancharia, with whom he had one daughter, Octavia Major (born circa 70s BCE). It is not known how the marriage ended; indeed, it is possible that Ancharia died in childbirth. In any case, Octavius was soon remarried to Atia, the niece of Julius Caesar. With her, he had two more children: Octavia Minor and Gaius Octavius, better known as Octavian (and later, of course, as Augustus; born 63 BCE).

In 58 BCE, Octavius died just as he was preparing to make a bid for the consulship, the highest office in the Roman Republic. In the year that passed between their father's death and their mother's remarriage, Octavia and Octavian lived beneath their mother's roof and were likely assigned male guardians – the names of these guardians have been lost, but, as Moore suggests, it is not unreasonable to think that Julius Caesar may have been among them. In 57 BCE, Atia remarried Lucius Martius Philippus, a man from a family of plebeian nobility of slightly higher standing than the Octavii. During this time, Octavia was educated in a manner befitting an adolescent girl in the late republican era. Like her mother, she was probably literate and would have been taught skills befitting the role of women in ancient Rome, such as wool-working and weaving. She also would have learned how to be a dutiful wife and mother, qualities that were expected of a Roman noblewoman.

Due to the patriarchal nature of ancient Roman society, it is impossible to separate Octavia's life from her relationships to men. However, by reading between the lines, it is possible to catch glimpses of the woman she might have been. Sometime before 54 BCE – when she would have been about 15 – her stepfather married her off to Gaius Claudius Marcellus, a member of the plebeian branch of the influential Claudian family, or gens Claudia. With him, she would have at least three children, each born in quick succession: Marcus Claudius Marcellus (born 42 BCE), Claudia Marcella Major (born 41 BCE), and Claudia Marcella Minor (born 40 BCE).

As a young woman, Octavia was viewed as a pawn to advance the political interests of her family. In 54 BCE, her great-uncle Caesar requested that she divorce her husband so that she could marry Pompey the Great (106 to 48 BCE), his rival with whom he had formed an uneasy alliance. Pompey had previously been married to Julia, Caesar's only acknowledged daughter and Octavia's cousin; her death in childbirth left Pompey not only as a widower, but the most eligible bachelor in Rome. Caesar knew he had to act fast if he were to reconsolidate their alliance with a marriage. Lacking any suitable single female relatives, he turned to the teenage Octavia and began pressuring her to divorce Marcellus. Divorce in ancient Rome was not nearly as taboo as it would become in Christian Europe, with Romans often setting aside their spouses for political reasons. Yet Octavia did not want to divorce Marcellus. Luckily, she would not have to – Pompey declined Caesar's proposal and married Cornelia Metella instead.

Over the next few years, as Caesar's power grew through his controversial conquest of Gaul, many in the Senate began to grow increasingly worried about his intentions. Marcellus was squarely in the anti-Caesar camp – after becoming consul in 50 BCE, he demanded that his wife's great-uncle give up his legions and return to Rome to answer for his crimes. When this did not work, Marcellus turned to Pompey, asking him to defend the Senate in the event of a civil war. This civil war broke out the following year, when Caesar crossed the Rubicon and invaded Italy. Octavia must have felt burdened by her divided loyalties. As a Roman woman, she was expected to show pietas – loyalty, devotion – to both her husband and the other male authority figures in her family. When Caesar entered Rome in January 49 BCE and was named dictator, it is possible that Octavia attempted to square this apparent contradiction by acting as mediator between the Senate and her great-uncle.

Though Marcellus opposed Caesar vocally, he crucially never took up arms against him. Partially because of this, Caesar pardoned Marcellus after his victory over Pompey at the Battle of Pharsalus in 48 BCE. Marcellus and Octavia seem to have remained in Caesar's good graces in the following years, as he accumulated more power and was named dictator for life. But then, on 15 March 44 BCE, Caesar was assassinated by a group of 60 senators led by Marcus Junius Brutus and Gaius Cassius Longinus.

The assassination of Julius Caesar marked another turning point for Octavia's family – for it was discovered that, in his will, Caesar had adopted Octavian and named him his heir. Octavia's younger brother, only 18 years old, was now, at a stroke, one of the most powerful men in Rome, inheriting not only Caesar's name but the loyalty of his soldiers. In 42 BCE, Octavian teamed up with one of Caesar's former lieutenants, Mark Antony, and defeated Brutus, Cassius, and some of the other assassins at the Battles of Philippi. In doing so, Octavian not only avenged Caesar but began to pave the way for his own rise to power.

In May 40 BCE, Marcellus died while Octavia was pregnant with their third daughter. Barely five months later, she was remarried, by Senatorial decree, to Mark Antony. By then, Octavian and Antony had entered an uneasy, power-sharing alliance called the Second Triumvirate. The empire was split between them; it was decided that Octavian would govern the western provinces, including Rome itself, while Antony took his seat of power in the East (the third triumvir, Marcus Lepidus, was given Africa). Octavia was married off to Antony to seal this alliance. She dutifully went East with her new husband, living with him in his mansion in Athens and travelling with him as he toured the eastern provinces. With him, Octavia would have two more daughters: Antonia Major (born 39 BCE) and Antonia Minor (born 36 BCE).

Despite his reputation as a rogue and a rake, Antony seems to have been loyal to Octavia for the first few years of their marriage, likely because he did not want to rock the boat between him and Octavian. Shortly after their wedding, Antony commissioned a series of gold, silver, and bronze coins depicting himself and Octavia. Meant to celebrate the dynastic alliance between Antony and Octavian, this marked the first time that an identifiable living woman featured on Roman coinage, as well as the first time that a woman's image was used to support her husband's political career. She is depicted on the coins wearing a modest, yet highly fashionable, hairstyle called the nodus (literally 'knot'), in which the hair is combed up and tied in a bun at the back of the head. The look presented her as the very image of austerity, as befitting a prominent Roman woman.

In 37 BCE, tensions flared up between Octavian and Antony, threatening to destroy their alliance and plunge Rome into another round of civil wars. Although she was pregnant with Antonia Minor, Octavia was called upon to go to Tarentum to mediate between her brother and her husband. Ancient commentators credit her with smoothing over the tensions, claiming that it was only through her calm demeanor that a compromise was reached and civil war avoided. She brokered a deal in which Octavian and Antony were each required to provide soldiers and ships to aid in the other's upcoming military campaign – Octavian's in Sicily, and Antony's in Parthia. For her role in patching up the shaky alliance, Octavia was celebrated throughout the Roman world and was called "a marvel of womankind" (quoted in Freisenbruch, 21).

In 36 BCE, Antony sent Octavia and their children to his estate in Rome on the pretext that he was about to embark on his Parthian campaign and wanted to make sure that they were somewhere safe. However, he undoubtedly had ulterior motives. Five years earlier, he had been seduced by the glamorous queen of Egypt, Cleopatra VII (69 BCE to 30 BCE). Their brief affair resulted in the births of twins, Cleopatra Selene II and Alexander Helios, born in the year of Antony's marriage to Octavia. Though he seems not to have had any dalliances with the queen during the first three years of his marriage, Antony rekindled their romance when he went back east on his Parthian campaign. Over a millennium later, in his play Antony and Cleopatra, William Shakespeare muses that it was Octavia's austerity, her "holy, cold, and still conversation" that drove Antony back into Cleopatra's arms (2.6, 153 to 154).

Whether or not there was any truth in this Shakespearean assertion, Octavia was nothing if not dutiful. In 35 BCE, she went to Antony's mansion in Athens with the money and resources she believed he needed for his campaign. When she arrived, she was greeted with a letter from her husband, ordering her to travel no further. Spurned, Octavia returned to Rome, where she continued to reside in Antony's house and care not only for her children but also for Antony's children from his previous marriages. Antony's treatment of Octavia only helped to turn the public against him, and he became "widely hated for wronging a woman of her fine quality" (quoted in Freisenbruch, 24). This hatred only worsened when Antony divorced Octavia in 32 BCE and sent men to Rome to turn her out of his house. Her image stopped appearing on eastern coinage; instead, Antony was depicted side by side with Cleopatra.

A master of public perception, Octavian did not waste this chance to use his sister's good name to muddy the reputation of his rival. In 35 BCE, hoping to contrast Antony's foreign queen with the virtuous Roman women of his own life, Octavian awarded three honors to both his sister Octavia and his wife Livia Drusilla (59 BCE to 29 CE). The first was the protection of sacrosanctitas, which made it illegal to verbally insult them – this marked the first time that this honor, usually granted to male politicians, was ever given to women. The second was the immunity from tutela, or male guardianship, meaning Octavia and Livia were free to look after their own affairs without male interference. Again, this was an unprecedented honor usually only given to Vestal Virgins. Finally, Octavian commissioned statues of them to be put on public display.

By elevating his sister and wife in such a way, Octavian made his own family look like the epitome of Roman virtue. In the meantime, he embarked on a smear campaign designed to make Antony appear effeminate and un-Roman. In 32 BCE, he illegally read Antony's will aloud before the Senate: apparently, Antony had bequeathed his fortunes to his children by Cleopatra rather than to his Roman-born children, and had requested to be buried not in Rome but by the queen's side in Alexandria. All of this succeeded in turning the hearts and minds of Romans against Antony. In 31 BCE, Octavian defeated Antony at the Battle of Actium. The next year, both Antony and Cleopatra committed suicide. By destroying his only serious rival, Octavian had become the sole master of the Roman world. A few years later, the Senate granted him the name Augustus ("Honored One") as well as the office of princeps ("First Citizen"), which effectively made him the first Roman emperor.

During the early years of Augustus's reign, Octavia was among the most prominent women of the Roman Empire, second only to Livia. Her sculpted likeness was everywhere. One marble bust thought to depict Octavia was discovered in the Italian town of Velletri; in the words of historian Annelise Freisenbruch, the sculpture shows "a serenely beautiful woman, with regular symmetrical features and large, heavy-lidded eyes, her neatly combed locks arranged into the nodus hairstyle, with just a few tendrils allowed to escape from the hairline above the ears" (26). Artists would have been less concerned with creating an exact likeness than with presenting Octavia as a symbol of virtue.

Ever since her divorce from Antony, Octavia lived with Augustus in his villa on the exclusive Palatine Hill in Rome. Aware of her brother's obsession with his public image, Octavia lent her skills to help present him as a humble man of the people, in order to conceal the true extent of his autocratic powers. Every day, Augustus wore a humble wool gown that had been woven for him by Octavia, Livia, and his daughter Julia the Elder. Hoping to foster a sense of domestic tranquility among the families of Rome, Augustus sometimes left his villa open to the public, where onlookers could see Livia and Octavia hard at work at the loom. Though this was clearly a choreographed publicity stunt, the message was clear – even the most powerful Roman women performed their feminine duties, as was expected of all wives and mothers.

In 27 BCE, Augustus refurbished a portico near the southern part of the Campus Martius and rededicated it to his sister. Known as the Portico of Octavia, it was an "elegant courtyard with cascading fountains and a garden that played host to a gallery of valuable paintings and sculpture" (Freisenbruch, 44). Octavia herself would sponsor the creation of several public buildings within her portico, including an assembly hall, lecture rooms, and a library, dedicated to her son. Octavia worked with some of the most eminent architects in Rome; in his treatise On Architecture, architect and engineer Vitruvius offers his thanks to Octavia for introducing him to Augustus and recommending his employment to the princeps.

By the mid-20s CE, it had become clear that Augustus and Livia were not going to have any children of their own. Though he was not yet 40, Augustus knew that he needed an heir and looked to the members of his extended family. There were two immediate candidates: Tiberius (42 BCE to 37 CE), Livia's son from a previous marriage, and Octavia's son, Marcus Claudius Marcellus. Although the boys were the same age, Marcellus soon emerged as the clear favorite – he was charming and popular, while Tiberius was gloomy and reclusive, and Marcellus was Augustus's blood relative, whereas Tiberius was only a stepson. In 25 BCE, Augustus seemed to seal the deal by marrying Marcellus to his daughter Julia. Octavia took on the prestigious but informal role as mother of the heir, which, for a time, allowed her to supersede even Livia as the 'first woman' of Rome.

But this did not last very long. In 23 BCE, Marcellus came down with a serious illness and died. The fact that he had been so young – only 19 – gave rise to rumors that he had been poisoned by Livia so Tiberius could take his place as heir. However, most scholars today believe that he did indeed die of natural causes. Whatever the true cause of Marcellus's death, Octavia was despondent. Her grief would be all-consuming, as highlighted by one memorable story. The poet Virgil (70 to 19 BCE) was reciting a passage from his epic poem The Aeneid before Augustus and his family. He came to the part where his hero, Aeneas, is in the underworld and sees a parade of Roman heroes. When it is revealed that young Marcellus's ghost is among them, Octavia reportedly fainted and collapsed into Augustus's lap.

For the last decade of her life, Octavia remained in seclusion in the confines of Augustus's villa. She rarely appeared at public events, and, when she did, she was always dressed in mourning clothes. Her absence from public life allowed Livia to once again rise above her and reclaim her role as 'first woman' of Rome. According to the philosopher Seneca, this caused a rift between the two women, with Octavia accusing Livia of profiting from the death of her son. In 11 BCE, Octavia died around the age of 58. She was the first person to be interred in the Mausoleum of Augustus, a grand tomb that her brother had erected to house the ashes of his family members. Octavia would be remembered as one of the most influential women in Roman history, who utilized her virtuous qualities and political talents to navigate the tumultuous years of civil war and rise to prominence alongside the birth of the empire.