Historical research is full of surprises and shocks. It may produce the blessings of which professor Hill has so eloquently reminded us; but it can also leave the student thwarted and disappointed. We cannot know when we embark on a subject what uncharted reefs and contrary currents are going to impede our course. A few years ago I rashly set out to work on the subject that the late professor Iorga called Byzance après Byzance. I hoped to tell of the fate of the Greeks and their neighbours in the orthodox Christian world when they passed under the absolute rule of the infidel ottoman sultan, during the centuries when they were tended by the orthodox patriarchate of Constantinople: to which one could apply, far more accurately than to the papacy, Hobbes’s description of ‘the ghost of the Roman Empire sitting crowned upon the ruins thereof’ – but the ruins were miserably dilapidated and the crown did not fit. I decided not to attempt a full history of the social life of the Christian minorities nor a detailed discussion of theological developments but to concentrate my study on the central organisation of the patriarchate itself. Even so it proved to be a daunting task.