Teutonic Order within the Holy Roman Empire. Ludwig von Erlichshausen, Grand Master from 1450 to 1467, took a more aggressive stance towards the confederation. He filed a lawsuit at the court of Emperor Frederick III. In response, the organization established a secret council to confer during the trial. The secret council held talks with Poland, and organized forces to revolt against the Teutonic Knights. The verdict of the Imperial court of 1453 declared the confederation illegal, however, the verdict was not recognized by the organization nor by Poland. Thirteen Years' War In February 1454, the Prussian Confederation rose against the Teutonic Order's rule. Gabriel von Baysen and Johannes von Baysen, now leading the confederation with the support of Jan de Jani and Mikołaj Szarlejski, both of the Clan of Ostoja, requested the protection of King Casimir IV Jagiellon of Poland, and the incorporation of the region to the Kingdom of Poland, to which the King agreed and signed an act of incorporation in Kraków in March 1454. They also asked for, and received, a guarantee of their continued city rights and privileges for the nobility. Delegates and officials of the Confederation pledged allegiance to the Polish King during the incorporation in Kraków, and also in the following months. The resulting Thirteen Years' War ended in the defeat of the Teutonic Order and the 1466 Second Peace of Thorn. The Order renounced any claims to the territories of Gdańsk/Eastern Pomerania and Chełmno Land, which were reintegrated with Poland, and the region of Elbląg and Malbork, and Warmia, which were also recognized as part of Poland. These regions formed the new Polish province of Royal Prussia, with some local rights of autonomy. Stibor of Poniec of the Clan of Ostoja become Lord of tregality of Malbork. Much of the eastern territories, in historic Prussia, remained with the Teutonic Order, although as a fief and protectorate of Poland, also considered an integral part of "one and indivisible" Kingdom of Poland. The Prussian Confederation, with its members now practically divided, ceased to exist as such. Aftermath Both the Polish and Teutonic sides agreed to seek the confirmation of the Second Peace of Thorn from Emperor Frederick III and Pope Paul II, but they also agreed that this confirmation would not be needed for validation of the treaty. Soon after, however, a dispute about the status of the Prince-Bishopric of Warmia started a smaller conflict