<P> (Valentinian) thought he had slain his master; he found that he had slain his protector: and he fell a helpless victim to the first conspiracy which was hatched against his throne . </P> <P> A rich senatorial aristocrat, Petronius Maximus, who had encouraged both murders, then seized the throne . He broke the engagement between Huneric, prince of the Vandals, and Princess Eudocia, and had time to send Avitus to ask for the help of the Visigoths in Gaul before the Vandals sailed to Italy . Petronius was unable to muster any effective response and was killed by a mob as he tried to flee the city . The Vandals entered Rome, and plundered it for two weeks . Despite the shortage of money for the defence of the state, considerable private wealth had accumulated since the previous sack in 410 . The Vandals sailed away with large amounts of treasure and also with the Princess Eudocia, who became the wife of one Vandal king and the mother of another . </P> <P> The Vandals conquered Sicily, and their fleet became a constant danger to Roman sea trade and to the coasts and islands of the western Mediterranean . </P> <P> Avitus, at the Visigothic court in Burdigala, declared himself Emperor . He moved on Rome with Visigothic support which gained his acceptance by Majorian and Ricimer, commanders of the remaining army of Italy . This was the first time that a barbarian kingdom had played a key role in the imperial succession . Avitus's son - in - law Sidonius wrote propaganda to present the Visigothic king Theoderic II as a reasonable man with whom a Roman regime could do business . Theoderic's payoff included precious metal from stripping the remaining public ornaments of Italy, and an unsupervised campaign in Hispania . There he not only defeated the Sueves, executing his brother - in - law Rechiar, but he also plundered Roman cities . The Burgundians expanded their kingdom in the Rhone valley and the Vandals took the remains of the Diocese of Africa . In 456 the Visigothic army was too heavily engaged in Hispania to be an effective threat to Italy, and Ricimer had just destroyed a pirate fleet of sixty Vandal ships; Majorian and Ricimer marched against Avitus and defeated him near Placentia . He was forced to become Bishop of Placentia, and died (possibly murdered) a few weeks later . </P>

What was not a result of the collapse of the western roman empire