On 9 June 68, amidst the growing opposition of the Senate and the army, Nero committed suicide, and with him the Julio-Claudian dynasty came to an end.
Chaos ensued, leading to a year of brutal civil war known as the Year of the Four Emperors, during which the four most influential generals in the Roman Empire—Galba, Otho, Vitellius and Vespasian—successively vied for the imperial power.
News of Nero's death reached Vespasian as he was preparing to besiege the city of Jerusalem.
Almost simultaneously the Senate had declared Galba, then governor of Hispania Tarraconensis (modern Spain), as Emperor of Rome.
Rather than continue his campaign, Vespasian decided to await further orders and send Titus to greet the new Emperor.
Before reaching Italy, however, Titus learnt that Galba had been murdered and replaced by Otho, the governor of Lusitania (modern Portugal).
At the same time, Vitellius and his armies in Germania had risen in revolt, and prepared to march on Rome, intent on overthrowing Otho.
Not wanting to risk being taken hostage by one side or the other, Titus abandoned the journey to Rome and rejoined his father in Judaea.

Otho and Vitellius realised the potential threat posed by the Flavian faction.
With four legions at his disposal, Vespasian commanded a strength of nearly 80,000 soldiers.
His position in Judaea further granted him the advantage of being nearest to the vital province of Egypt, which controlled the grain supply to Rome.
His brother Titus Flavius Sabinus II, as city prefect, commanded the entire city garrison of Rome.
Tensions among the Flavian troops ran high, but as long as Galba and Otho remained in power, Vespasian refused to take action.
When Otho was defeated by Vitellius at the First Battle of Bedriacum, however, the armies in Judaea and Egypt took matters into their own hands and declared Vespasian emperor on 1 July 69.
Vespasian accepted, and entered an alliance with Gaius Licinius Mucianus, the governor of Syria, against Vitellius.
A strong force drawn from the Judaean and Syrian legions marched on Rome under the command of Mucianus, while Vespasian himself traveled to Alexandria, leaving Titus in charge of ending the Jewish rebellion.

In Rome, meanwhile, Domitian was placed under house arrest by Vitellius, as a safeguard against future Flavian aggression.
Support for the old emperor was waning, however, as more legions throughout the empire pledged their allegiance to Vespasian.
On 24 October 69 the forces of Vitellius and Vespasian clashed at the Second Battle of Bedriacum, which ended in a crushing defeat for the armies of Vitellius.
In despair, he attempted to negotiate a surrender.
Terms of peace, including a voluntary abdication, were agreed upon with Titus Flavius Sabinus II, but the soldiers of the Praetorian Guard—the imperial bodyguard—considered such a resignation disgraceful, and prevented Vitellius from carrying out the treaty.
On the morning of 18 December, the emperor appeared to deposit the imperial insignia at the Temple of Concord, but at the last minute retraced his steps to the imperial palace.
In the confusion, the leading men of the state gathered at Sabinus' house, proclaiming Vespasian Emperor, but the multitude dispersed when Vitellian cohorts clashed with the armed escort of Sabinus, who was forced to retreat to the Capitoline Hill.
During the night, he was joined by his relatives, including Domitian.
The armies of Mucianus were nearing Rome, but the besieged Flavian party did not hold out for longer than a day.
On 19 December, Vitellianists burst onto the Capitol, and in the resulting skirmish, Sabinus was captured and executed.
Domitian himself managed to escape by disguising himself as a worshipper of Isis, and spent the night in safety with one of his father's supporters.
By the afternoon of 20 December, Vitellius was dead, his armies having been defeated by the Flavian legions.
With nothing more to be feared from the enemy, Domitian came forward to meet the invading forces; he was universally saluted by the title of Caesar, and the mass of troops conducted him
On 9 June 68, amidst the growing opposition of the Senate and the army, Nero committed suicide, and with him the Julio-Claudian dynasty came to an end. Chaos ensued, leading to a year of brutal civil war known as the Year of the Four Emperors, during which the four most influential generals in the Roman Empire—Galba, Otho, Vitellius and Vespasian—successively vied for the imperial power. News of Nero's death reached Vespasian as he was preparing to besiege the city of Jerusalem. Almost simultaneously the Senate had declared Galba, then governor of Hispania Tarraconensis (modern Spain), as Emperor of Rome. Rather than continue his campaign, Vespasian decided to await further orders and send Titus to greet the new Emperor. Before reaching Italy, however, Titus learnt that Galba had been murdered and replaced by Otho, the governor of Lusitania (modern Portugal). At the same time, Vitellius and his armies in Germania had risen in revolt, and prepared to march on Rome, intent on overthrowing Otho. Not wanting to risk being taken hostage by one side or the other, Titus abandoned the journey to Rome and rejoined his father in Judaea.
Otho and Vitellius realised the potential threat posed by the Flavian faction. With four legions at his disposal, Vespasian commanded a strength of nearly 80,000 soldiers. His position in Judaea further granted him the advantage of being nearest to the vital province of Egypt, which controlled the grain supply to Rome. His brother Titus Flavius Sabinus II, as city prefect, commanded the entire city garrison of Rome. Tensions among the Flavian troops ran high, but as long as Galba and Otho remained in power, Vespasian refused to take action. When Otho was defeated by Vitellius at the First Battle of Bedriacum, however, the armies in Judaea and Egypt took matters into their own hands and declared Vespasian emperor on 1 July 69. Vespasian accepted, and entered an alliance with Gaius Licinius Mucianus, the governor of Syria, against Vitellius. A strong force drawn from the Judaean and Syrian legions marched on Rome under the command of Mucianus, while Vespasian himself traveled to Alexandria, leaving Titus in charge of ending the Jewish rebellion.
In Rome, meanwhile, Domitian was placed under house arrest by Vitellius, as a safeguard against future Flavian aggression. Support for the old emperor was waning, however, as more legions throughout the empire pledged their allegiance to Vespasian. On 24 October 69 the forces of Vitellius and Vespasian clashed at the Second Battle of Bedriacum, which ended in a crushing defeat for the armies of Vitellius. In despair, he attempted to negotiate a surrender. Terms of peace, including a voluntary abdication, were agreed upon with Titus Flavius Sabinus II, but the soldiers of the Praetorian Guard—the imperial bodyguard—considered such a resignation disgraceful, and prevented Vitellius from carrying out the treaty. On the morning of 18 December, the emperor appeared to deposit the imperial insignia at the Temple of Concord, but at the last minute retraced his steps to the imperial palace. In the confusion, the leading men of the state gathered at Sabinus' house, proclaiming Vespasian Emperor, but the multitude dispersed when Vitellian cohorts clashed with the armed escort of Sabinus, who was forced to retreat to the Capitoline Hill. During the night, he was joined by his relatives, including Domitian. The armies of Mucianus were nearing Rome, but the besieged Flavian party did not hold out for longer than a day. On 19 December, Vitellianists burst onto the Capitol, and in the resulting skirmish, Sabinus was captured and executed. Domitian himself managed to escape by disguising himself as a worshipper of Isis, and spent the night in safety with one of his father's supporters. By the afternoon of 20 December, Vitellius was dead, his armies having been defeated by the Flavian legions. With nothing more to be feared from the enemy, Domitian came forward to meet the invading forces; he was universally saluted by the title of Caesar, and the mass of troops conducted him
Flavian dynasty