The earlier years of his power were associated with many stirring events which exercised no inconsiderable influence on the state of learning. For example, his skilful playing off of Duke Galeazzo Maria Sforza of Milan against Ferrante, King of Naples, led to greater attention being directed by the Florentines to Neapolitan and Milanese affairs, with the result that humanists and artists from both these places paid frequent visits to Florence, where they were welcomed by Lorenzo as his guests. Then when the revolt of the small city of Volterra from Florentine rule was suppressed by Lorenzo's agents, with a rigorous severity that cast a stain on their master's name, owing to many unoffending scholars having suffered to the extent of losing their all, Lorenzo made noble amends. Not only did he generously assist the inhabitants to repair their losses, not only did he make grants to the local scholars and send them copies of many of the codices in his own library to supply the loss of their books which had been burned by the soldiery, but he purchased large estates in the neighborhood, that the citizens might benefit by his residence among them. In this way, too, he brought the Volterran scholars into more intimate relations with the Florentine humanists, and thus contributed to the further diffusion of the benefits of the Renaissance. All was not plain sailing, however, as regards the progress of the "New Learning." Despite his efforts, Lorenzo could not prevent its development being checked during the papal-Neapolitan quarrel with Florence. That war originated in a dispute with Pope Sixtus IV, who kept Italy in a ferment during the whole duration of his pontificate, 1471-1484. Were no other proof forthcoming of Lorenzo's marvellous diplomatic genius than this one fact, that he checkmated the political schemes of Sixtus, and finally so neutralized his influence as to render him wellnigh impotent for evil-doing, such an achievement was sufficient to stamp him one of the greatest masters of statecraft Europe has known. In any estimate of his ability we must take into account the unsatisfactory character of many of the instruments wherewith he had to achieve his purposes, and also the fact that he had neither a great army at his back with which to enforce the fulfilment of treaty obligations--for Florence never was a city of soldiers--nor had he the prestige of an official position to lend weight to his words. To all intents and purposes he was a private citizen of the Florentine republic. Yet such was the dynamic power of the man's marvellous personality, and the reputation he had earned, even in his early years, for supreme prescience and far-reaching diplomatic subtlety, that far and wide he was regarded as the greatest force in Italian politics. Sixtus sallied forth to crush; he returned to the Vatican a crushed and a discredited man, to die of sheer chagrin over his defeat by Lorenzo in his designs upon Ferrara.