On 4 September 476 AD, the Germanic chieftain Odoacer deposed the last Western Roman emperor, Romulus Augustulus, and sent the imperial regalia to Constantinople, marking the conventional end of the Western Roman Empire.
Historians debate the precision of this date — the empire had been fracturing for decades under barbarian incursions, economic collapse, and political instability — but 476 became the standard marker. The Eastern Roman Empire (Byzantine Empire) survived for nearly another thousand years until the fall of Constantinople in 1453.
Rome's collapse reshaped European civilisation, ushering in the Early Middle Ages and breaking the Mediterranean political unity that had lasted for five centuries.