Another campaign was led by Emperor Lucius Verus in 162–165, after Vologases IV of Parthia had invaded Armenia and installed his chief general on its throne. To counter the Parthian threat, Verus set out for the east. His army won significant victories and retook the capital. Sohaemus, a Roman citizen of Armenian heritage, was installed as the new client king. But during an epidemic within the Roman forces, Parthians retook most of their lost territory in 166. Sohaemus retreated to Syria, and the Arsacid's dynasty was restored to power over Armenia.