On Tuesday, 29 May 1453, an old story was ended. The last heir of Constantine the Great lay dead on the battlefield; and an infidel Sultan had entered in triumph into the city which Constantine had founded to be the capital of the Christian Empire. There was no longer an Emperor reigning in the Sacred Palace to symbolize to the Faithful of the East the majesty and authority of Almighty God. The Church of Constantinople, for more than a thousand years the partner of the Orthodox State, became the Church of a subject people, dependent upon the whims of a Muslim master.
Sir Steven Runciman, The Great Church in Captivity.