Which event is associated with the collapse of the Roman Empire?

The event associated with the collapse of the Roman Empire is the sacking of the city of Rome by the Goths. This significant event symbolizes the decline of Roman power and authority in the West, marking a turning point in the history of the Roman Empire. The sack occurred in 410 CE under the leadership of Alaric, the king of the Visigoths, and represents not only a physical capture of the city but also a psychological blow to Roman prestige. The act of a foreign power breaching the walls of Rome, which had long been considered invulnerable, marked a clear indication that the Empire was in decline and could no longer defend itself effectively from external threats.

In contrast, other events mentioned do not directly correlate to the fall of the Empire. For instance, the formation of the Byzantine Empire outright represents a continuation of Roman governance rather than a collapse. The establishment of the Pax Romana refers to a period of relative peace and stability across the empire and does not indicate decline. Lastly, the signing of the Treaty of Verdun occurred much later and relates to the division of the Carolingian Empire, which is separate from Roman history.