The Radziwill family (Polish pronunciation: [rad?i'viw]; Lithuanian: Radvila; Belarusian: ????????, Radzivil; German: Radziwill) is a powerful magnate 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 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, Polish, Belarusian, German as well as general European history and culture.
The Radziwill family received the title of Reichsfürst (prince) from the Holy Roman Empire.
The Nesvizh Castle complex, maintained by the family between the 16th century and 1939, is a UNESCO World Heritage site.