From the Council of Ephesus

If He had chosen the great city of Rome, the change in the world would be ascribed to the influence of her citizens. If He had been the son of the Emperor, His benefits would have been attributed to the latter’s power. But that we might acknowledge the work of God in the transformation of the whole earth, He chose a poor mother and a birthplace poorer still. Council of Ephesus, A.D. 431