From his uncle, Justinian inherited ongoing hostilities with the Sassanid Empire. In 530 the Persian forces suffered a double defeat at Dara and Satala, but the next year saw the defeat of Roman forces under Belisarius near Callinicum. Justinian then tried to make alliance with the Axumites of Ethiopia and the Himyarites of Yemen against the Persians, but this failed. When king Kavadh I of Persia died (September 531), Justinian concluded an "Eternal Peace" (which cost him 11,000 pounds of gold) with his successor Khosrau I (532). Having thus secured his eastern frontier, Justinian turned his attention to the West, where Germanic kingdoms had been established in the territories of the former Western Roman Empire.