The ancestor of Czech historiography, the author of the first "Czech Chronicle" ("Chronica boemorum") is the Prague canon, dean of the chapter of the Cathedral of St. Vita - Kozma Prague. In the extensive literature devoted to the "Czech Chronicle" of Kozma, the glory of "Herodotus of Czech History" was established behind him. The meaning of the "Chronicle" of Kozma of Prague is determined by three points. Firstly, covering the history of the Czech land from ancient times to the first quarter of the XII century. (The Chronicle ends with the year of the death of its author - 1125) and being the first chronicle of the Czech Republic, this work, despite some inaccuracies in chronology and the author's quite understandable subjectivity, on many issues remains the only written source of early feudal Czech Republic. Secondly, the Chronicle largely predetermined the development of the Czech chronicle in subsequent times. Thirdly, it goes beyond the framework of Czech national historiography, revealing the relationship between various states (Germany, Poland, Hungary) in the X-XII centuries, and its high, for that time, scientific level and the significance of the events described in it put the author of the Chronicle among the most prominent chroniclers of medieval Europe.