In 421, Bahram V succeeded his father Yazdegerd I, who shortly before he had been killed, began a persecution of Christians as reprisal for attacks against Zoroastrian temples by Christians during his reign; Bahram continued this persecution, during which many died. Among them there was James Intercisus, a political counsellor of Yazdegerd's, who had converted to Zoroastrianism but then converted back to Christianity. So, when Persian ambassadors reached the Roman court to ask for the fugitives, Theodosius choose to break the peace and declare war, rather than giving them back.