As a prominent member of a state noble family, rusag's nobility (Serbo-Croatian: rusaška gospoda), he bore a title of duke (vojvoda), and had a seat in Drežnica.
[1] The Drežnica valley of the river Drežanka, a tributary of the Neretva, is 21 km long, and it cut between Čabulja in the south and Čvrsnica in the north.
From 1357, together with western Hum, area came under the Hungarian king Louis I control as a dowry of his wife Elizabeta, daughter of Stjepan II Kotromanić.
[1] In addition to the contents of the inscription, which mentions duke Mastan and his two sons Radoslav and Miroslav, other two reliable written sources about them and the family exist.
Another source, dated 8 October 1382, is the decision made by Dubrovnik council, which allowed Radoslav Mesnović to deposit grain and honey in the city.