The second of three barbarian sacks of Rome, the sack of 455 is at the hands of the Vandals, who are at war with the usurping Western Roman Emperor Petronius Maximus.In 455, the Vandal king Geiseric sails his powerful fleet from the capital in Carthage, up the Tiber, finally sacking Rome.

The murder and usurption of the previous Emperor Valentinian III by Petronius Maximus that same year is seen by Geiseric as an invalidation of his 442 peace treaty with Valentinian.Upon the Vandal arrival, according to the chronicler Prosper, Pope Leo I implores Geiseric not to destroy the ancient city or murder its inhabitants.

Geiseric agrees and the gates of Rome are thrown open to him and his men.

Maximus, who flees rather than fight the Vandal warlord, is killed by a Roman mob outside the city.It is accepted that Geiseric looted great amounts of treasure from the city, and also took the Empress Licinia Eudoxia, Valentinian's widow, and her daughters hostage.

One of these daughters is Eudocia, who was later to marry Geiseric's son Huneric.There is, however, some debate over the severity of the Vandal sack.

The sack of 455 is generally seen by historians as being more thorough than the Visigothic sack of 410, because the Vandals plundered Rome for fourteen days whereas the Visigoths spent only three days in the city.The cause of most controversy, however, is the claim that the sack was relatively 'clean', in that there was little murder and violence, and the Vandals did not burn the buildings of the city.

This interpretation seems to stem from Prosper's claim that Leo the Great managed to persuade Geiseric to refrain from violence.