The second half of the last century is characterized by an increased interest in the literature of Ancient and Medieval Russia. Since the 40s, a large number of fundamental studies dedicated to various works before the time of Peter the Great have appeared. This attention was accompanied by a more thorough study of the Church Slavonic language itself: its spelling, morphology and, of course, vocabulary, as evidenced by the work begun in the 70s on compiling a dictionary of the Russian language of the 11–17th centuries.