Throughout much of his reign his troops were engaged in a defensive struggle against Persia in the east and a successful war against the barbarians in the west. Believing that they had lost their initial vigour, he hoped to revive the old Roman empire. His general, Belisarius, crushed the Vandals in Africa (533) and the Ostrogoths in Italy (535–53), making Ravenna the centre of government. His greater claim to fame lay in his domestic policy in which he was strongly influenced by his powerful wife, Theodora. He reformed provincial administration and in his Corpus Juris Civilis he codified 4652 imperial ordinances (Codex), summarized the views of the best legal writers (Digest), and added a handbook for students (Institutes). A passionately orthodox Christian, he fought pagans and heretics. His lasting memorial is the Church of St Sophia in Constantinople.