He was renowned for his military achievements and as a talented politician. He took part in various conflicts against Muscovy, the Cossacks and the Tatars. Achieving around 30 military victories, he has been referred as the Lithuanian Hercules.
As a member of influential Radziwiłł family, Jerzy worked to increase his family estate. With his death it was inherited by his only son Mikołaj "the Red" Radziwiłł. He had two daughters, of which the younger Barbara Radziwiłł became mistress and later queen to King of Poland and Grand Duke of Lithuania Zygmunt II August, which greatly strengthened the Radziwiłł family's position in Poland and Lithuania.