The hundred-year period ending in 1025, from the reign of the Emperor Constantine VII to that of Basil II 'the Bulgar-Slayer', encompassed the last great era of Byzantine aggression and dominance in the Near East and Balkans. During that time, a succession of soldier-emperors challenged and defeated an array of opponents on land and at sea and reconquered vast swathes of territory. At the heart of the Emperors' forces were the professional, highly mobile Tagmata or Imperial Guard regiments, originally formed to guard the Emperors person in the capital but invariably deployed as elite combat...