This episode of "Crash Course World History" explores the debated timeline of Rome's fall, positing it extended into the 15th century with the Eastern Roman Empire, also known as the Byzantine Empire. The video, featuring author John Green, delves into common historical theories including the barbarian invasions and internal decline due to imperial overreach and the integration of mercenaries. It highlights key events and figures like Constantine, Justinian, and Theodora, while also addressing religious transformations impacting Roman identity and governance. This content aligns with social studies curricula, providing an in-depth analysis of the Roman and Byzantine empires' influence on modern legal and cultural structures. Part of the "Crash Course World History" series.