Abstract: During the interwar period, Prague was truly an academic capital of emigration. A unique scientific environment that formed therein a century ago was favorable for the study of Russian literature, including the ancient period. Among the philologists, who emigrated to Czechoslovakia, was Alfred Bem, known to modern science as a talented researcher of the works of Pushkin, Dostoevsky, Blok, Gumilyov and Mayakovsky. However, hardly anyone remembers Bem as Medievalist. The article analyzes the “Lectures” on the history of Old Russian literature (up to the mid XVII century) read to the students of Russian Pedagogical Institute named after Jan Amos Komenský in Prague in the winter semester of 1923 that have been nearly forgotten by now. These are the sheer bibliographic rarity. The circulation of this unique publication is small, just a few copies taken by duplicating machine from the typewritten original, which contains typos and corrections made by the author. “Lectures...” – a full textbook on the history of Russian literature of the XI – first half of the XVII centuries. A significant part of is dedicated to the “Tale of Bygone Years”. A. L. Bem’s view of the "Nestorian Chronicle” reflected in the Prague “Lectures...” is analyzed within the framework of studying the extensive historiographical topic of the “Research of Old Russian Literature in Czechoslovakia in the 1920s – 1930s”. This defines the novelty of this article. The conclusion is made that Alfred Bem made a considerable contribution to the study of the major Russian chronicle, provided in-depth and accurate characteristics to the “Tale of Bygone Years”, determining its historical and literary role. His contemplations on the genre and stylistic uniqueness of the “Tale” have subsequently found reflection in the works of Russian and foreign Medievalists. He also paid special attention to the history of the Corpus, thereby touching upon the question that is yet to be resolved.