Wikipedia
The Radziwiłł family (; ; ; ) is an aristocratic family originating from the Grand Duchy of Lithuania and later the Crown of the Kingdom of Poland. The descendants of Kristinas Astikas, a Lithuanian and a close associate of the 14th century Lithuanian ruler Vytautas, were highly prominent for centuries, first in the Grand Duchy of Lithuania, later in the Polish–Lithuanian Commonwealth and the Kingdom of Prussia. The family has produced many individuals notable in Lithuanian, Belarusian, Polish, German (particularly Prussian) and general European history and culture. The Radziwiłł family received the title of Reichsfürst (prince, , , ), from the Holy Roman Empire.
The Nesvizh Castle complex, maintained by the family in Belarus between the 16th century and 1939, is a UNESCO World Heritage site. The countries of Belarus, Finland, Lithuania, Poland, Russian Federation, and Ukraine jointly nominated its family archives to the UNESCO Memory of the World Register in 2008, and they were inscribed on the Register in 2009.