Original sentence: Unlike Lazar who died in battle along with most of his army, Vuk managed to to survive and preserve his army which latter gave material to popular Serbian folk belief ( represented in folk epic poems and tales ) that he betrayed Lazar in order to become supreme ruler of Serbia, belief that is refuted by modern day Serbian historians
Edited sentence: Unlike Lazar who died in battle along with most of his army, Vuk managed to to survive and preserve his army which latter gave material for popular Serbian folk tradition ( represented in folk epic poems and tales ) that he betrayed Lazar in order to become supreme ruler of Serbia, the theory that is refuted by modern day Serbian historians