Later, after his daughter, Barbara Radziwiłł married the Grand Duke of Lithuania and King of Poland Sigismund II Augustus in 1547, the power and influence of the family grew immensely.
Senere, efter hans datter Barbara Radziwiłł giftede sig med storfyrsten af Litauen og konge af Polen Sigismund II August i 1547, voksede familiens magt og indflydelse.