Decades of civil war during the 1st century BC had contributed greatly to the demise of the old aristocracy of Rome, which was gradually replaced in prominence by a new Italian nobility during the early part of the 1st century AD.
One such family were the Flavians, or gens Flavia, which rose from relative obscurity to prominence in just four generations, acquiring wealth and status under the emperors of the Julio-Claudian dynasty.
Vespasian's grandfather, Titus Flavius Petro, had served as a centurion under Pompey during Caesar's civil war.
His military career ended in disgrace when he fled the battlefield at the Battle of Pharsalus in 48 BC.
Nevertheless, Petro managed to improve his status by marrying the extremely wealthy Tertulla, whose fortune guaranteed the upward mobility of Petro's son Titus Flavius Sabinus I. Sabinus himself amassed further wealth and possible equestrian status through his services as tax collector in Asia and banker in Helvetia (modern Switzerland).
By marrying Vespasia Polla he allied himself to the more prestigious patrician gens Vespasia, ensuring the elevation of his sons Titus Flavius Sabinus II and Vespasian to the senatorial rank.

Around 38 AD, Vespasian married Domitilla the Elder, the daughter of an equestrian from Ferentium.
They had two sons, Titus Flavius Vespasianus (born in 39) and Titus Flavius Domitianus (born in 51), and a daughter, Domitilla (born in 45).
Domitilla the Elder died before Vespasian became emperor.
Thereafter his mistress Caenis was his wife in all but name until she died in 74.
The political career of Vespasian included the offices of quaestor, aedile and praetor, and culminated with a consulship in 51, the year Domitian was born.
As a military commander, he gained early renown by participating in the Roman invasion of Britain in 43.
Nevertheless, ancient sources allege poverty for the Flavian family at the time of Domitian's upbringing, even claiming Vespasian had fallen into disrepute under the emperors Caligula (37–41) and Nero (54–68).
Modern history has refuted these claims, suggesting these stories were later circulated under Flavian rule as part of a propaganda campaign to diminish success under the less reputable Emperors of the Julio-Claudian dynasty, and maximize achievements under Emperor Claudius (41–54) and his son Britannicus.
By all appearances, imperial favour for the Flavians was high throughout the 40s and 60s.
While Titus received a court education in the company of Britannicus, Vespasian pursued a successful political and military career.
Following a prolonged period of retirement during the 50s, he returned to public office under Nero, serving as proconsul of the Africa province in 63, and accompanying the emperor during an official tour of Greece in 66.

From c. 57 to 59, Titus was a military tribune in Germania, and later served in Britannia.
His first wife, Arrecina Tertulla, died two years after their marriage, in 65.
Titus then took a new wife of a more distinguished family, Marcia Furnilla.
However, Marcia's family was closely linked to the opposition to Emperor Nero.
Her uncle Barea Soranus and his daughter Servilia were among those who were killed after the failed Pisonian conspiracy of 65.
Some modern historians theorize that Titus divorced his wife because of her family's connection to the conspiracy.
He never remarried.
Titus appears to have had multiple daughters, at least one of them by Marcia Furnilla.
The only one known to have survived to adulthood was Julia Flavia, perhaps Titus's child by Arrecina, whose mother was also named Julia.
During this period Titus also practiced law and attained the rank of quaestor.

In 66, the Jews of the Judaea Province revolted against the Roman Empire.
Cestius Gallus, the legate of Syria, was forced to retreat from Jerusalem and defeated at the battle of Beth-Horon.
The pro-Roman king Agrippa II and his sister Berenice fled the city to Galilee where they later gave themselves up to the Romans.
Nero appointed Vespasian to put down the rebellion, and dispatched him to the region at once with the
Decades of civil war during the 1st century BC had contributed greatly to the demise of the old aristocracy of Rome, which was gradually replaced in prominence by a new Italian nobility during the early part of the 1st century AD. One such family were the Flavians, or gens Flavia, which rose from relative obscurity to prominence in just four generations, acquiring wealth and status under the emperors of the Julio-Claudian dynasty. Vespasian's grandfather, Titus Flavius Petro, had served as a centurion under Pompey during Caesar's civil war. His military career ended in disgrace when he fled the battlefield at the Battle of Pharsalus in 48 BC. Nevertheless, Petro managed to improve his status by marrying the extremely wealthy Tertulla, whose fortune guaranteed the upward mobility of Petro's son Titus Flavius Sabinus I. Sabinus himself amassed further wealth and possible equestrian status through his services as tax collector in Asia and banker in Helvetia (modern Switzerland). By marrying Vespasia Polla he allied himself to the more prestigious patrician gens Vespasia, ensuring the elevation of his sons Titus Flavius Sabinus II and Vespasian to the senatorial rank.
Around 38 AD, Vespasian married Domitilla the Elder, the daughter of an equestrian from Ferentium. They had two sons, Titus Flavius Vespasianus (born in 39) and Titus Flavius Domitianus (born in 51), and a daughter, Domitilla (born in 45). Domitilla the Elder died before Vespasian became emperor. Thereafter his mistress Caenis was his wife in all but name until she died in 74. The political career of Vespasian included the offices of quaestor, aedile and praetor, and culminated with a consulship in 51, the year Domitian was born. As a military commander, he gained early renown by participating in the Roman invasion of Britain in 43. Nevertheless, ancient sources allege poverty for the Flavian family at the time of Domitian's upbringing, even claiming Vespasian had fallen into disrepute under the emperors Caligula (37–41) and Nero (54–68). Modern history has refuted these claims, suggesting these stories were later circulated under Flavian rule as part of a propaganda campaign to diminish success under the less reputable Emperors of the Julio-Claudian dynasty, and maximize achievements under Emperor Claudius (41–54) and his son Britannicus. By all appearances, imperial favour for the Flavians was high throughout the 40s and 60s. While Titus received a court education in the company of Britannicus, Vespasian pursued a successful political and military career. Following a prolonged period of retirement during the 50s, he returned to public office under Nero, serving as proconsul of the Africa province in 63, and accompanying the emperor during an official tour of Greece in 66.
From c. 57 to 59, Titus was a military tribune in Germania, and later served in Britannia. His first wife, Arrecina Tertulla, died two years after their marriage, in 65. Titus then took a new wife of a more distinguished family, Marcia Furnilla. However, Marcia's family was closely linked to the opposition to Emperor Nero. Her uncle Barea Soranus and his daughter Servilia were among those who were killed after the failed Pisonian conspiracy of 65. Some modern historians theorize that Titus divorced his wife because of her family's connection to the conspiracy. He never remarried. Titus appears to have had multiple daughters, at least one of them by Marcia Furnilla. The only one known to have survived to adulthood was Julia Flavia, perhaps Titus's child by Arrecina, whose mother was also named Julia. During this period Titus also practiced law and attained the rank of quaestor.
In 66, the Jews of the Judaea Province revolted against the Roman Empire. Cestius Gallus, the legate of Syria, was forced to retreat from Jerusalem and defeated at the battle of Beth-Horon. The pro-Roman king Agrippa II and his sister Berenice fled the city to Galilee where they later gave themselves up to the Romans. Nero appointed Vespasian to put down the rebellion, and dispatched him to the region at once with the 
Flavian dynasty