RADZIWILL. - An ancient noble family of Lithuanian origin, united in the 16th century by ties of kinship with the Jagelloni. Its progenitor was Ostyk, but it was his son R. Ostykowicz, palatine of Troki and castellan of Wilno, who gave the family its name.
In the 16th century a large part of the family’s members adhered to the Reformation. Its eminent representative was NICOLA, known as the Black (1515-65), marshal and grand chancellor of the grand duchy of Lithuania, trusted counsellor of Sigismondo Augusto, king of Poland, who received the title of prince of the Empire in 1547, a dignity also confirmed for Poland in 1569. He supported the Calvinists and in 1563 had the Bible translated by Socinians published. His son NICOLA CRISTOFORO (1549-1616), under the influence of Card. Osio, converted to Catholicism and stood beside King Sigismondo III in introducing the Counter-Reformation into Poland. GIORGIO (1556-1600), another son of Nicola the Black, became a cardinal in 1586; MICHELE CASIMIRO (1625-80) held diplomatic posts (embassy to the Pope in 1679). In the 19th century EDMONDO (1842-95), a member of the German Centre party and deputy, subsequently took the Benedictine habit at Beuron.