The Birbsteins (Biebersteins) supported King Sigmund during the Hussite Wars (1419–1434). Frýdlant was apprehended by the Hussites in 1428. Between 1428 and 1433, the town was raided several times. Frydlant castle and town, also called Frydlant Manor went to Emperor Ferdinand I when Christopher, the last of the line of the Birbsteins, died in 1551. The castle went into the Redern family when Bedřich bought it in 1558. Since the ruler set the religion for an area at that time, Bedřich made Protestant churches and closed the Catholic church in Hejnice that had been the destination for religious pilgrimages. Several new villages were established and the production of linen cloth resulted in an economic boom during the initial years of the Redern family. Marco Spazzio di Lancio, an Italian architect hired by the family, expanded the castle in the 16th century.