After his father's death, a throne struggle broke out between Konstantin, Stefan and their cousin Vladislav II, evolving into the two years long civil war. He was killed in the battle fighting his brother, who went on to defeat Vladislav, too, and gained the Serbian throne as Stefan Uros III, better known as Stefan Decanski.

Life of Konstantin, who may even be canonized in Middle Ages, was obscured even in medieval chronicles while today is almost completely forgotten. Nearly all data on him