Surnamed Barbarossa (Red-beard), of the house of Swabia, emperor of the Holy Roman Empire (q. v .) from 1152 till 1190; "a magnificent, magnanimous man, the greatest of all the Kaisers"; his reign is the most brilliant in the annals of the empire, and he himself among the most honoured of German heroes; his vast empire he ruled with iron rigour, quelling its rival factions and extending his sovereign rights to Poland, Hungary, Denmark, and Burgundy; the great struggle of his reign, however, was with Pope Alexander III. and the Lombard cities, whose right to independence he acknowledged by the treaty of Constanz; he "died some unknown sudden death" at 70 in the crusade against Saladin and the Moslem power; his lifelong ambition was to secure the independence of the empire, and to subdue the States of Italy to the imperial sway (1123-1190).