Nada Klaič was born on the 21st of july 1920 and died on the 2nd of august 1988. In 1943 she took her university degree in history and became assistant at the Faculty of Arts in Zagreb. She took her doctor's degree in 1946 with the dissertation Political and economic regulation of Slavonia during Arpadovič. After university teacher habilitation in 1955 and after associate professor in 1961 she became in 1969 regular professor on chair for Croatian history. She collaborated in commissions for both first editions of History of Nations of Yugoslavia. Anew she reviewed documents from the period of national sovereigns which she partly published in four booklets. In searching historical truths she surprised with new theses. Among 15 monographs and over a hundred treatises to be pointed out are The History of Croats in the Early Middle Ages (1971) and The History of Croats in the Late Middle Ages (1976) which are her life-works.