455CE

455 CE was a year in the 5th century. In the Western Roman Empire, this year saw significant turmoil. The emperor Valentinian III was assassinated in March, bringing an end to his reign and further destabilizing the already weakened empire. Following his death, various figures vied for power, leading to a rapid succession of emperors. Petronius Maximus briefly took the imperial title but was quickly overthrown and killed. In June, the Vandals, led by their king Gaiseric, sailed from North Africa and sacked Rome for two weeks. This event further diminished the prestige and power of the Western Roman Empire.

Meanwhile, in the Eastern Roman Empire, Theodosius II was still emperor. The Hunnic Empire under Attila had been a major threat in previous years, but Attila died in 453 CE, and his empire began to fragment, reducing its immediate pressure on the Eastern Roman Empire. However, the ongoing instability in the West continued to be a major concern for the Byzantine state. In the East, the Sasanian Empire remained a significant power, though not directly involved in the events of Rome.