the relationship between King-Duke (after Vytautas/Witold left this world and the unification opposition lost it's influence) was Father-Son.
So, when the King died in Poland the crown was offered to Kazimierz Jagiellonczyk grand duke of Lithuania -who at first refused because the Polish King was not an absolute rule whilst the Grand Duke was.
So, when the King died in Poland the crown was offered to Kazimierz Jagiellonczyk grand duke of Lithuania -who at first refused because the Polish King was not an absolute rule whilst the Grand Duke was.