In the 16th century, Protestant Reformation movements made deep inroads into Polish Christianity and the resulting Reformation in Poland involved a number of different denominations. The policies of religious tolerance that developed in Poland were nearly unique in Europe at that time and many who fled regions torn by religious strife found refuge in Poland. The reigns of King Sigismund I the Old (1506–1548) and King Sigismund II Augustus (1548–1572) witnessed an intense cultivation of culture and science (a Golden Age of the Renaissance in Poland), of which the astronomer Nicolaus Copernicus (1473–1543) is the best known representative. Jan Kochanowski (1530–1584) was a poet and the premier artistic personality of the period. In 1525, during the reign of Sigismund I, the Teutonic Order was secularized and Duke Albert performed an act of homage before the Polish king (the Prussian Homage) for his fief, the Duchy of Prussia. Mazovia was finally fully incorporated into the Polish Crown in 1529.