Complex sentence: One of these provinces, Silesia, was granted to Bolesław III's eldest son, Władysław II the Exile, and was subsequently divided among his descendants and successors, until they died out in 1675.
Split into simpler sentences: One of these provinces, Silesia, was granted to Bolesław III's eldest son, Władysław II the Exile. Soon it was subsequently divided among his descendants and successors, until the last died out in 1675.