Byzantium:

For 1,123 years, Constantinople remained the capital of the Byzantine Empire - the longest-lived and most continuously inspired Christian empire in the world. In this, the third and final volume of John Julius Norwich's magnificent and moving history, he tells of the dire consequences of the defeat by the Seljuk Turks at the battle of Manzikert in 1071; of the Fourth Crusade, whose Crusaders - led by the octogenarian Doge of Venice - turned their attention away from the Holy Places to hurl themselves against Constantinople, sacking the city and setting up a succession of Frankish thugs on the imperial throne; and of the two-hundred-year struggle by the restored Empire against the inexorable advance of the Ottoman Turks.