 When his brothers died, Biagio found himself sole proprietor of Trpanj, and in order to ensure that Trpanj as a whole remained in his family he made Trpanj an indivisible legal entity protected by a “fideicomis”, a sort of a testamentary trust.Frano Gondola, who was an Austrian marshal, wrote from Vienna on 22 May 1672 to his friend Marco Bassegli to ask him to get the Republic to name him Duke and as a result to name Trpanj Dukedom of St. Michael of Trpanj.This was necessary because of his position in Vienna.