 The King of Croatia and Dalmatia Petar Krešimir IV (1058–1074) expanded its kingdom "on land and on sea".In his deed of donation to the convent of Saint Krševan in Zadar in 1069, it is stated that he donated the island of Maun, situated "in our Dalmatian sea" ("in nostro dalmatico mari").The Duke of the Croatian Royal Navy, Rusin, is mentioned at the time and the fact that the very title of Duke could be borne only by governmental dignitaries is proof of the navy importance.