Boleslav I the Cruel (? -
972), was the Duke of
Bohemia from 935 to 972.
His father was
Vratislav I of Bohemia, Duke of Bohemia. Boleslav I had a son named
Boleslav II the Pious[?] of Bohemia, Duke of Bohemia, and a sister named Dobrava/
Dubrawka of Bohemia .
He murdered his older brother Václav/Wenceslas, the first Duke of Bohemia to convert to Christianity.