Part 3/12:
Yet, Focus made a significant blunder. Years earlier, Maurice had befriended the Persian King Kosro II after helping him regain his throne. Upon learning of Maurice's death, Kosro decided to avenge his friend by invading Roman territories, thereby reigniting the fierce rivalry between the Byzantines and Persians. The Byzantine Empire, under Focus's poor leadership, disintegrated rapidly. By 608 CE, Persia had regained control over significant territorial portions of the Eastern Roman Empire, including Damascus and Jerusalem, while the Slavs overran the Balkans.