After the death of Frederic II., the Imperial throne long remained vacant. For twenty-three years no king of the Romans was definitively proclaimed in Germany, and sixty-two years elapsed before any prince came to Rome to assume the crown of the Empire. Therefore during this interval the Ghibelline party was left to its own resources, and its leaders tried to maintain their feudal rights by employing their forces and prestige against all communes and small potentates enjoying no chance of gaining the Imperial protection. Hence petty tyrants began to arise on all sides, Ghibelline lords for the most part, who, notwithstanding the many defeats endured by the aristocracy in Italy, derived new and unexpected advantages from the changed conditions of the times. Another factor of this result was the new mode of warfare. Men-at-arms were now the chief strength of an army, and these mounted soldiers, cased as well as their horses, in heavy armour and armed with long spears, were able to overcome infantry before the latter's halberds could come into play. But a lengthy training was required for cavalry service, and it was increasingly difficult for artisans or merchants to pursue the military career to any effect, whereas war was becoming the chief occupation of the nobles. In fact, many of the leading patricians were acquiring a reputation in the new mode of war, gaining followers, and by taking the command of small companies gradually rising to power, and aspiring to become tyrants. For this and other reasons, to be made clearer farther on, nearly all the Lombard cities, and some of those in Central Italy, were now losing their independence. [Illustration: PALAZZO VECCHIO, FLORENCE. [_To face page 241._]