Simon Sebag Montefiore uncovers the three identities of the City some call the Centre of the World. Byzantium, Constantinople and Istanbul. This one metropolis has been the capital city of three empires - Roman, Byzantine and Ottoman. Each brought its own faiths, Gods and traditions, and each left its mark on the city in its architecture, traditions and in the living faith-communities who still populate this vast modern metropolis of 14 million people.