What event characterized the cultural transitions at the start of the Early Medieval period?

The fall of Rome marks a significant cultural transition at the start of the Early Medieval period, often referred to as the Dark Ages. This event, occurring in the late 5th century, resulted in the fragmentation of the Roman Empire, leading to the decline of centralized power and the rise of localized rule. Consequently, the once-thriving urban centers began to crumble, giving way to rural economies and feudal systems.

This shift profoundly influenced art, culture, and society, as the continuity of classical Roman traditions gave way to a mix of Roman, Germanic, and eventually Christian practices. The loss of Roman infrastructure and trade networks led to a decline in literacy and large-scale art production, further contributing to the perception of this era as 'dark.' Cultural identities evolved, as new languages and customs arose from the remnants of Roman influences intermixed with those of migrating tribes.

In contrast, the other options do not directly pertain to the Early Medieval period: the Industrial Revolution occurred much later, scientific discoveries were not prominent until the Renaissance, and city-states were more characteristic of the Renaissance and Medieval period in Italy rather than the early transitions following the fall of Rome.