a combination of factors including economic instability, external invasions, political corruption, and the rise of powerful barbarian tribes such as the Visigoths, Vandals, and Ostrogoths. The empire had been in decline for centuries, with its territory shrinking and its military weakened. The final blow came in 476 AD when the Germanic chieftain Odoacer deposed the last Roman emperor, Romulus Augustulus, effectively ending the Western Roman Empire. The eastern half of the empire, known as the Byzantine Empire, continued to exist for another thousand years until it fell to the Ottoman Turks in 1453.
