Aragonese claimant to the throne of Naples, his next important act was to convene a congress of the representatives of Christian princes at Mantua for joint action against the Turks. On 26 September 1459 he called for a new crusade against the Ottomans and on 14 January 1460 he proclaimed the official crusade that was to last for three years. His long progress to the place of assembly resembled a triumphal procession, and the Council of Mantua of 1459, a complete failure as regards its ostensible object of mounting a crusade, at least showed that the impotence of Christendom was not owing to the Pope. The Pope, however, influenced Vlad III Dracula, whom he held in high regard, in starting a war against Sultan Mehmed II of Turkey. This conflict at its peak involved the Wallachians trying to assassinate the Sultan (see The Night Attack). On his return from the congress, Pius II spent a considerable time in his native district of Siena, where he was joined by his erstwhile host in Mantua Ludovico Gonzaga. Pius described his delight with country life in very pleasing language. Passages such as those and others where he marvels at landscapes and other natural beauties, or stories about his dog Musetta, were to be expurged from the first edition of his Commentaries published in 1584 as embarrassingly unfitting, coming from the pen of a pope. He was recalled to Rome by the disturbances occasioned by Tiburzio di Maso, who was ultimately seized and executed. In the struggle for the Kingdom of Naples between the supporters of the House of Aragon and the House of Anjou, the Papal States were at this time troubled by rebellious barons and marauding condottieri, whom he gradually, though momentarily, quelled. The Neapolitan War was also concluded by the success of the Pope's ally the Aragonese Ferdinand. In particular, the Pope engaged for most of his reign in what looked like a personal war against Sigismondo Pandolfo Malatesta, Lord of Rimini, with the result of the almost complete submission of that condottiero. Pius II also tried mediation in the Thirteen Years' War of 1454–66 between Poland and the Teutonic Knights, but, when he failed to achieve success, cast an anathema over Polish and Prussians both. Pius II was also engaged in a series of disputes with King George of Bohemia and Archduke Sigismund of Austria (who was excommunicated for having