Petronius Maximus, the ruler of the Western Roman Empire, was stoned to death by a mob as he fled Rome ahead of the arrival of a Vandal force that sacked the city.

Petronius Maximus was Roman emperor of the West for two and a half months in 455. A wealthy senator and a prominent aristocrat, he was instrumental in the murders of the Western Roman magister militum, Aëtius, and the Western Roman emperor, Valentinian III.

In modern historiography, the Western Roman Empire was the western provinces of the Roman Empire, collectively, during any period in which they were administered separately from the eastern provinces by a separate, independent imperial court. Particularly during the period from AD 395 to 476, there were separate, coequal courts dividing the governance of the empire into the Western provinces and the Eastern provinces with a distinct imperial succession in the separate courts. The terms Western Roman Empire and Eastern Roman Empire were coined in modern times to describe political entities that were de facto independent; contemporary Romans did not consider the Empire to have been split into two empires but viewed it as a single polity governed by two imperial courts for administrative expediency. The Western Empire collapsed in 476, and the Western imperial court in Ravenna disappeared by AD 554, at the end of Justinian's Gothic War.

The Vandals were a Germanic people who were first reported in the written records as inhabitants of what is now Poland, during the period of the Roman Empire. Much later, in the fifth century, a group of Vandals led by kings established Vandal kingdoms first within the Iberian Peninsula, and then in the western Mediterranean islands, and North Africa.

The sack of Rome in 455 was carried out by the Vandals led by their king Gaiseric.