On the example of the manuscript De Rebus Dalmaticis (1602), written by Dinko Zavorović, a humanist and historian from Šibenik, this work analyzes the elements which had the most important influence on the appearance of critical historiography at the turn of the 16th to the 17th century. Particular attention is awarded to the specific methodology of Zavorović's work with historical sources and topics. The first part of the thesis analyzes the specific methodological approach to the historical sources quoted in the work De Rebus Dalmaticis, which are divided into narrative, diplomatic and epigraphic sources. The second part of the work analyzes the influences of Zavorović's specific late-humanistic methodology of working with historical sources on the topics of secular and ecclesiastical history, as well as on the topics on the ethnogenesis of Slavs and their cultural history. The research results have proved that the work De Rebus Dalmaticis by Dinko Zavorović is an important link between the traditional humanist and late humanist pre-critical historiography, as well as an unquestionable turning point in the development of historiography, the significance of which is based upon these of a more progressive methodological approach to historical sources and topics. The research results enable better evaluation of the Humanist historiographical production in Croatia and establishing of more precise divide between the traditional and the critical historiography.