When we refer to someone as ‘Byzantine’ we usually mean guileful or too complicated and labyrinthine in manner or speech. Perhaps the term is ill-applied: Byzantium, the medieval Greek city on the Bosporus which the Roman Emperor Constantine I renamed Constantinople, was not in essence an unfathomable, over-hierarchical or manipulative sort of place. It flourished for more than 1,000 years, until the Ottoman Turkish onslaught in the 15th century, by dint of its ‘extraordinary resilience and self-confidence’, says Judith Herrin, a leading Byzantinist. The northern Italian city of Ravenna, with its wondrous mosaicked churches and gilded mausolea that miraculously survived the aerial bombardments of the second world war, was manifestly also a Byzantine city.