Tvrtko's reign saw the rise to power of the Kosača family, of whom Vlatko Vuković had already by that time begun to rule much of Hum;during Sandalj Hranić's (1392-1435)and Herceg Stjepan Vukčić Kosača's (1435-1466) time and that of the latters sons, until1482, Hum was entirely governed by the family.