 Complete the following phrase:  In 1525 during the Protestant Reformation, in accordance to the Treaty of Kraków, the Grand Master of the Teutonic Knights, Albert, secularized the orders Prussian territory, becoming Albert, Duke of Prussia. As the region had been an integral part of the Kingdom of Poland since the Second Peace of Thorn 1466, King of Poland Sigismund I the Old, as its suzerain, granted the territory as a hereditary fief of Poland to Duke Albert per the Treaty of Kraków, a decision that was sealed by the 