After the crowning of Ladislaus as the Hungarian King in Zadar in 1403, and in political maneuvering against his arch political rival and enemy, the King Sigismund, he made Hrvoje his deputy for Dalmatia territory, as promised, calling him his Vicar General for the regions of Sclavonia (in partibus Sclavonie). He was also named Duke of Split, and given possessions on the islands of Brač, Hvar and Korčula. From then on he carried the title of "Grand Duke of Bosnia and Knyaz of Donji Kraji, Duke of Split, regent of Dalmatia and Croatia", or as title visible on coins duke was able to mint in Split read in . In 1406 Hrvoje Vukčić Hrvatinić fortified and strengthened Prozor Fortress over the Vrlika valley in Croatia, also given to him by Ladislaus of Naples.<br>